286 motherboard repair - VARTA battery leaked

well hello everyone and welcome back to adrian's digital basement it's a friday night at least for me when i'm recording this and i'm home in the basement i'm not out on the town having fun i figured i should do something a little bit relaxing after a long week and what i'm gonna do is try to repair a motherboard this is a 286 motherboard at motherboard nothing too unusual but what is common about this particular motherboard is it has suffered battery damage from a leaky varda or nicad battery i got this motherboard and the battery had already been removed so i don't exactly know what brand it was but we can be pretty sure it was a rechargeable niket and it has leaked on the board and it has caused some damage so in this video i'm going to try to repair it now leaky nicad batteries are super common they seem to be in vogue to be used on pcs and amigas and all sorts of other machines starting in the kind of mid 80s or so into the 90s some pcs were lucky enough to have alkaline batteries like the ibm 5170 sitting off to my left here those don't generally generally leak but they can but these nicads that are on these 286s 3d6s some 46 boards by the pentium era things had switched to cr2032s and it's extremely unlikely those are going to leak but if you have one of these in storage something like in this era 286 through 486 and you haven't removed the battery you got to go get that machine and get that battery out of there unfortunately it's probably too late hopefully you did that years ago especially if you have an amiga 2000 or any of the other amigas for that matter or 2 000 3000 or 4000 because it's leek-o-matic on all of those and it's very destructive on the 2000. anyhow this has been a very long intro it's my way of saying let's see if i can get this board working i mean you know it might actually work i haven't even tested but it's impossible there's broken chases over here so let's see if i can get this thing working and without further ado let's get right to it [Music] i think everyone knows the drill for repairing these types of problems when you have potentially bad traces i'm going to be using the end and star usb or hdmi microscope of course i have a power supply and at power supply for powering up the board i got plenty of wire wrap wire which is a perfect barge wire got my multimeter for of course checking continuity and last but not least i have a set of extremely extremely sharp test leads these have little caps on the end because once you pull those off they're like needle points which are excellent at figuring out where the trace is broken because you can poke right through the solder mask highly recommended and this was also a donation from a viewer so thank you very much for this if you're watching and of course i have my adult beverage it's a concoction of i don't know some kind of a 7up cherry thing and uh some vodka yes only drink if you are of age that's my disclaimer all right think of the first thing you got to do i'll situate myself a little bit better let's take a look with the microscope at the damage on this board normally i would be using the overhead camera but i think i'm just going to move this out of the way right now because it's going to be pretty hard to see trace damage even with the good zoom lens that's on the panasonic actually there's one more thing to do so this motherboard which was given to me exactly like this completely untested is a 286 12 megahertz vlsi chipset pretty much run-of-the-mill i mean what is kind of cool about this board it's got well two different types of dram sockets right here plus it has these extra sockets here i'll have to go look at the manual but i wouldn't be surprised if these large dram chips here are for the type where two chips equals one megabyte and you could potentially install four megabytes of ram right here in this spot i'm assuming that these unpopulated sockets here are for parity memory one two three four five six seven eight nine okay that's not the case because these have nine chips that already has parity memory what exactly is this i don't know have to check the manual but currently the ram that's in here is good old 256k times one bit so we have a total of one megabyte of memory right here the fact that there is another socket kind of overlaid or i don't know what's the right word shifted by one pin has one extra pin that implies that you could install one megabyte times one bit chips and also have four megs of ram here or i guess two megs plus uh 512k so two and a half megabytes so there's a lot of flexibility with this particular motherboard when it comes to the way you install the ram which is always appreciated the one thing i need to do before we start is this thing still has the case standoffs in it and i hate working on a motherboard with those installed so i'm gonna pop those out right now now i'd actually love to hear people's tips and tricks for a good way to get these out of the board the way i've always done it is i grab needle nose pliers like this and i just squeeze try to get these out and it's always a little fiddly depends on how big the hole is some motherboards like the little hole that these plug into is probably slightly under spec i mean what is this spec exactly all of these are just copies of ibm's motherboard right the ibm 5160 and 5170 motherboard at least from a form factor perspective and yeah this motherboard appears to have the holes that are a little bit too small what i'm going to try is this which i have no idea what this is but it's like an extruded piece of plastic with a hole in the middle so and that does absolutely nothing this is like a plastic straw or something why is that in my little thing of tools i don't know but it looks like i have another one here which i think has a magnet on one end and nope it is not small enough to easily get that out obviously if i had something with a small enough hole in the middle you could just put it over these things and it would squeeze it together and then you could slide it right out okay so i just got one out and yes the holes are really small so you really got to kind of jam these to get them out you know when we went to atx motherboards we switched to metal standoffs all over the board you didn't have to use these stupid things anymore which are a huge huge pain in the butt now that has a nice small hole that one popped out very easily why exactly oh it's oblong for a little bit of flexibility and positioning but that one's not that one is that one's not all right anyways enough chit chat i'll get the rest of these off alrighty the motherboard is under the microscope and i have turned up the bitrate on the video capture so i am hoping that it is not super janky because of that so what you see right here this horrible looking thing is one of the terminals of the battery obviously it's the positive terminal and that solder is very very corroded now i have already bathed this entire thing in vinegar to try to remove corrosion but as you can see here let me move this down a little bit there is still lots of it we also have little bubbles in the solder mask right here now that doesn't necessarily mean that the trace is broken same thing right here ultimately that is a little bit of corrosion underneath the solder mask so i should try to scrape that away i was doing a lot of scraping when i had the the vinegar all over this thing now that trace while it looked really black there it may not actually be bad but very hard to say obviously this scraping reveals that there is a big chunk with corrosion there now there's also some corrosion right here on this via and then right here is one of the typical problems we have corrosion and it may actually cause a break between that trace and that via there although i'm not sure that looks like it might be okay meanwhile up here there is a trace that is simply gone from this board it is just eaten away so at the minimum i'm gonna have to barge over this trace and there's just a tiny bit right here goes under here yep so this right here is probably okay there's probably copper under there yep see there's copper obviously these resistors have seen better days but i'm sure they're actually fine we could just sort of scrape this crud off of them but you can see that even these traces up here have little spots of corrosion so we're going to have to check all those with those pointy probes for the multimeter just to check that there is actually continuity if we move away from that bad area things over here look pretty good i can see that there's a tiny bit of corrosion notice on the jumper right there there's a little bit and these legs here are slightly corroded as well it's kind of amusing because like i said i bathed this whole board this whole area here in vinegar but it wasn't very reactive over here but that that's pretty crusty yeah this one too crustomatic but as we get a little further away these diodes they're in perfect shape and not really seeing any more problems over here what's this going on right there nope that's just crap on the top that's fine back over near the scene of the crime got some crap going on here on these two resistors does scrape right off though but if we keep going over here okay so there's this damage okay so this is by the battery again i mentioned of course that this is just missing all together so for sure those are broken and that's a power line or a power trace right this brings power over to the isa slots now let's move down here a little bit now strangely enough while there's obviously signs of corrosion here i mean look at this this poor crystal is not looking super hot definitely the traces over here seem to be in good shape look at this black stuff on here yucky same thing over here it's really funny when i had this uh when i was initially cleaning this i really noticed that there was all this green stuff down here and this crap on these resistors look there's even some in this via right here but if we go down further things are looking pretty good like this i see right here looks totally fine no issues it seems very much localized up at the top of the board now as i had mentioned these are power traces and then these ones that run along the top here are things that bring signals from like over here to over there like or this stuff here i think is connected to the chipset through those traces even though it's up here near the battery and keyboard connector it's not really related i don't think it's really related to that stuff all right time to survey the underside of the board here so there's a tiny bit of corrosion on the what is the keyboard connector these pins here are part of the keyboard connector see what's going on there i think those are not broken it is just a little bit of corrosion under the solder mask so it probably is a good idea to try to scrape it away and then paint this with a little bit of um not resin well obviously you could use like a new solder mask i actually bought some of that it's like a uv curing stuff i always just use nail polish like clear clear nail polish seems to work well for me things look pretty good over here obviously you can see a little bit of the corrosion kind of poking through there and on this via next door as well look at that yucky but generally things aren't too bad uh that would be one of the battery connections on the underside that one is the other one extra customatic all right i think it's time to break out the multimeter and start to figure out which traces are actually bad so i'm gonna pop off these and i'm gonna stick on the super pointy sharp i've jabbed myself plenty of time with them leads for the multimeter i am going to grab the 99 ipa and i'm just going to spray it on this area here the reason why is just kind of clean away some of that crust that i had uh sprayed around by by scratching making it a little bit easier to see although it's a little bit glarey now why don't we start at the top let's check out these traces right up along the top here and i'm just gonna poke into them we're gonna see if they have continuity okay all right clearly that is working there that was not easy at all this solder mask does not like to be poked through i think what i'm going to do is i'm going to grab one of these glass fiber pens sent in by one of my lovely viewers and i'm going to try to scratch or polish away some of this uh terrible looking stuff here all right so as you can see i made a large mess let me clean that up all right and check that out now that looks so good i can see very clearly where the traces are good and where they're bad all right i'm just gonna do a little bit more of this polishing on here especially like around these resistors here just to try to clean them up okay here we are post cleaning so i noticed that this resistor right here see how that that uh trace comes off of it i think it's actually connected but i rubbed off the solder mask here in case it's not then i can jump from like right here on the resistor to right there then this trace here is the one that goes underneath them and as you can see that's that's one of the traces that's completely gone and it does try to come back right here but it goes under the keyboard connector and uh i wasn't able to really sand any of that away right there i might be able to scrape it away oh you know i can wow look at that that shouldn't really be that color um looks like rust almost doesn't it um okay well anyways i might need to try to figure out where exactly that is going it might be like this one right here and maybe what i can do is i can put the multimeter on right there on that capacitor and then see if i can just touch it to right there i don't know that looks pretty crusty right there but maybe there's some good copper there these three traces up at the top here uh even though there's a little bit of corrosion i guess still right there pretty much they're looking perfect so now that they're cleaned off oh actually no this one doesn't look good right through here these traces down here well i think this is probably connected and i can test by touching like the edge of the via there and then test the trace over here make sure it's connected there's a little bit eaten away there but that's not super bad and this looks not too bad either it's a little crusty on the inside there and now we have this section here which we knew was really bad this power section so i've kind of cleaned off here and here and there and there so i should be able to just jump over this entire bad section here i'm just going to try to scrape away this green stuff at least but it doesn't really matter and we're definitely going to jump over this missing trace here so we're going to go from there to over there and i'm really thinking that down in this area even though you know there's little spots here it's probably totally fine and you do have to remember anytime you scrape off the solder mask like i just did right there you should touch that up with a little bit of lacquer nail polish or anything to like cover that that copper up again otherwise it can corrode and turn green i have the multimeter back on again and um let's just check for continuity on some of this stuff here now that i have easily removed the solder mask so it's very simple to do this so yeah see there's no continuity there but right over here there is so on the via if i go to the edge over here there is actually continuity as well and inside this via there we go that little spot right there is bothering me so i'm gonna scratch at it with the uh tweezers there to get that black spot off there we go all right so obviously it goes without saying that none of this stuff is connected right because of uh this is this is not a trace at all there's just literally nothing there so there's nothing there there there or there so we have three traces to fix clearly all of this stuff is totally fine here no issues there also here no issues this is good and what kind of sucks is unfortunately this corrosion is pretty insidious like i don't think it you know now that i've neutralized it it's not like it's uh going to take over the whole board or anything like that oops there we go that's still good but you know it's it's definitely caused a lot of damage it's not unfixable but it's a pain in the butt now if we had schematics for this board it would make fixing it a lot easier because anytime there were traces that were hidden underneath things we could just find out where they were going by tracing them back to the chips they were coming from but we don't have that luxury so we kind of have to do it the old-fashioned way by just using our eyes all right it's time to do some soldering right now and you can see that the alcohol is still on the board it's sort of spreading right there it's coming out from under the keyboard connector so i'm going to grab the hot air i'm going to try to dry some of that and i just have 150c on here coming out of the hot air rework station and the reason why i'm drying it out is because i want to use some flux on this area and it's probably a good idea just to get rid of the alcohol first if possible ah look at that i just noticed something that there's actually a little bit of corrosion inside this 8-bit slot right there what's kind of amazing the fact that there was corrosion in that slot means that like it was able to kind of crawl up the slot especially because i don't see any corrosion down there at the bottom but somehow it made its way up there luckily you could still buy these connectors so if i was really wanting to save this motherboard or save that slot i could replace that if for some reason in the future it it came apart ultimately even if that slot goes bad you still have seven other slots that that work all right the first one i'm going to try to fix is this one now it's actually not broken but i just don't trust how crusty it looks there if i move the light around it doesn't get any better so um even though there is continuity i'm just going to bridge over that part right there so i'm just adding a little flux using a syringe to do it and let's see about tinning these a little bit that doesn't work very well at all all right the barge is on and i i can't believe this mess here my um the flux i'm using is really not good i don't know what's wrong with it it's this stuff here this no clean flux but it just seems to suck i don't know what the deal is with it so we left a real mess here on on all this so just clean it up a little bit by scratching it but uh that is on there and then what i'm gonna do to get this little extra piece off here is i'm just going to try to grab it first and i'm just going to break it off there we go and instead of using this stuff i'm going to go back to my flux pen which is rosin so we have one broken trace down and uh i don't know four or five more to go i'm gonna put a little rosin flux right here where we know we're gonna be working there and there this stuff is hard to clean off but it works amazingly well whoops i'll do this side next well that's not good shouldn't be too hard to clean that off there we go oh boy oh boy all right this is uh yeah it's kind of getting frustrating here okay that is good this this flux is disgusting and really gooey all right we're getting there it's ugly because of all the flux um it's it's pretty frustrating doing this kind of micro soldering so i really do recommend if you don't want to go through all this heartache you should try to figure out where the traces start and end on the bottom side of the board and just join it there like this thick trace almost certainly goes from the power connector to one of the slots and you could just run a wire under the underside just not even deal with this whole section just sand it off like i just did and call that good because this is just a huge pain in the butt to work with and look i still have one more trace to go through all right i think i have this one on i'm just gonna cut it off i find that uh trying to twist it off actually kind of peels it off the board a little bit so let's see are these actually soldered on at all yep that one is this thick one here yep that is that one is as well so is that one okay let's get some alcohol on here try to clean that up a little bit that is ugly but it's ugly and it's not touching together so it should work i do have to say one thing that i don't know if this board even works and you know maybe i should have tested it ahead of time and uh the problem is is after this work i'm doing right now the board may still be broken and it might be broken for a completely unrelated reason to what's going on in this part of the board so i'm just getting some alcohol on there and then i'm using a toothbrush and i'm just trying to kind of clean up that flux mess that's underneath there and then i'm using a little bit of a paper towel here to try to sop up that flux that's on there see how it's turning to a kind of flex color there and then what we should do now is just double check that we have continuity now so from there to here we do uh let's see well i don't have much to go on there but there to there there to there we have continuity let's see if we have a short to these we do not obviously this is a big thick wire here that i soldered on there so that has continuity and it's not shorted to that one it's not shorted to this one on the top here that little beeping you heard was a capacitor charging or something like that and there to there is good now as well and of course i can go from there to these other ones just to double check it's not shorted yeah obviously it's not and then we know up here well it was already connected even before i did this wire so this was just like reinforcement for in case uh down the road that it actually breaks oh and actually while we're here let's uh let's go from there to the resistor so yeah we're good we're getting we're getting continuity alrighty so the last bad trace is this one now where exactly does it go let's try to figure that out is it one of these under here it could be it could also be these here it doesn't really look like uh the one on this side here actually goes to doesn't line up exactly with any of these right here so thanks to the very pointy probes it is actually this one right here that's coming down next to p51 now it goes under the power connector so i can't exactly see where that is going so i think what i'm going to do is scrape off some of the solder mask right here and i will solder a wire from there and i'll just run it across the board with insulation over to the other part where it's not broken okay and what i did is i ran the little barge wire under those resistors just to kind of hold it in place there so it goes on to the middle trace right here so let's see how i can do this i'm going to have to do left-handed soldering which i really don't enjoy so you can see that is the drop of flux that i have on there just twist this a little bit there we go okay that is actually on there nice all right uh the final thing i do before i paint up the board is i wanted to remove the battery terminals and it's always a little bit of a trick i had to kind of do it off of a magnifying glass because the old solder was such a disaster but as you can see i got it out and i think um all is good here look at this disgusting mess this is what happens to the the nice solder that was used on this board when it gets eaten away by that nicad battery juice yik so there's that terminal and up here is the other one and oh it's so crusty look at this nasty yeah this one really took the brunt of the corrosion luckily this one's just ground and if you want to connect a new battery up to the board you can just uh put it on anywhere the positive one is not too bad if i just clean up this kind of mud that is there but yeah look at that it's not too bad all right i have successfully soldered on terminals to both of these and they're in there properly so i think it is time for lacquer because there's all sorts of exposed copper now you could just tin all of this but i like to use the lacquer it's just the way i like to do it and yes it is just clear nail polish varnish this stuff is very durable if you think about the wear and tear it goes through when it's on people's fingers not to mention well i'm almost dropping it there not to mention you can get this off pretty easily with acetone that's what i like about it okay the lacquer is going on you can see it still has a sheen to it i'm not going to bother with that trace it's all corroded but i did paint right on the edge there and uh painted over there oh there's some exposed parts i see there we go it's now covered up there's a couple spots on the back here i just want to make sure that it is covered up and there's another one right down here all righty i think we're ready for some testing well what i'm going to do is let this dry a little bit that lacquer it's not like it's conductive or anything i don't think i'll let that dry up and then we can test this see if this board even works all that work on the repair and this thing might be dead and unlike a commodore amiga as an example where it's easy well not easy but you can you know what chips to replace their schematic stuff like that these types of boards there's no schematics hopefully this 286 board works and um all this work wasn't for nothing but you got to do the work to figure out if the board even works right all righty we are ready for testing i think i'm ready for testing this is where this video is either going to go down the path of it works or it doesn't work and if it doesn't work well i haven't had good luck fixing motherboards that didn't have obvious damage like this one when there were other things wrong with them yeah typically i kind of got stuck especially if it appears totally dead so what i'm going to do is i'm going to use this which is a postcard not the kind you mail this shows post codes as in when you turn on the pc it starts to post i don't know what that term actually means maybe that's an acronym i don't know but uh as the bios here starts to run through diagnostics so to speak like basic rudimentary diagnostics on the computer it prints codes to a particular i o address which this card looks at so anytime it sees io address being written over the bus well the bus will show it then it just displays the code this all happens from the moment you turn on the computer and the bios starts executing code all the way to the point you end up initializing the vga card which is right here we won't plug that in right away the postcode will then hand off to the rest of the bios sequence so we are going to plug in the postcode or postcard into the motherboard it does have a little wire here which is for the speaker and the reason is for the speaker is because you can get useful beep codes from a lot of bios's if the computer is executing code but say the ram is bad and it can't initialize the video you will hear beep code so it's kind of like a sign of life other thing the postcode postcard does is it shows you the voltage rail so for instance like this bad trace here probably meant one of the voltage rails was not working maybe i should have tested that before i did all this work i don't know why i didn't do it but i didn't do make sure if you buy one of these and they are only a few dollars that you don't plug them in backwards isa cards always go in with the circuitry facing the power connector or the keyboard connector on a normal at motherboard like this you can of course plug this in backwards you do not want to do that it causes damage i know this because i did that on my xd ide here i think it was this one actually that i did it on which is why i have labels that say towards back towards front because i put it in backwards and it caused damage all right so the power supply is ready to go i will turn this so the post codes are visible power connector is connected no cards are inserted here we go okay great sign everyone basically if the computer weren't executing any code then i'm going to unplug the speaker so we don't hear the beeping if the processor weren't running or the bios chips weren't in there you would not get anything on here it would just say dash dash which is what it did when i first turn on the machine in fact i'll turn it off and we'll turn it back on and for a split second you will see dash dash on there there it is and then the code start and that's because this displays dash dash until the bios writes to that io port for the postcode and that's what you're seeing here so it's reading 1a now it's reading 30. that means this computer is trying to work the beeping that we heard was almost certainly because there's no video card and that is very typical behavior of these early bios's they do not like having no video card and they will beep beep but it could be other problems as well so what we're going to do is we're going to plug in the video card i'll plug it in behind the postcard so we can continue to see the codes there we go click click and i have the video card plugged into the open source scan converter let's turn this on and see what happens okay we're getting beep codes right away and it hasn't even initialized the video like we're just getting the test pattern from the open source scan converter it does say 30 so what we need to do is let this sit a second and just make sure it stops on 30 and then we need to go look up the bios beep codes so or the postcode as well this is an ami bios 286 which means it should be easy to find the postcodes oh one thing to consider by the way and i might have talked about this before there are no postcodes on xt machines well maybe some do but the ibm 5160 5150 and like compact xt machines do not have postcodes there's no particular reason why they don't i think it's because the bios is small and there's not enough space but they could write postcodes this sort of seemed to come about in the 286 era starting with the ibm 5170 a pcat all the clones and everything beyond that of course has post codes and this card as you notice here has a pci interface as well so yes it works on newer computers and there are even something which i just learned the other day and thanks to sev one of my friends um there are machines which output postcodes on the parallel port and those would be laptops and things where you can't just plug a card in like this but all right it's stuck at 30. let's go look up what 30 is and we might need to go look up what that beeping beep code was as well because it had a different number during the beep code all right we're looking at the ami bios postcodes here this should do the trick i definitely have looked at this uh site before let's zoom in a little bit this is way too small uh ami amit what uh prior to 1990 well this says 1989. so i'd say that this counts right here it says 30 ready to start virtual mode test what let's power cycle the computer here and let's see what it beeps on um it's working let's go back to uh yeah that's a working machine uh let's switch this back to the video input uh there it is okay that's pretty hilarious why exactly did this not work the first time and now it works but it is working now and that tick tick tick was the ami bios counting the memory and we can see on there on the screen it has one meg of memory it's getting an error about the floppy drive whatever whatever let's turn this off we're going to connect up the xt ide here i will not plug it in backwards and these card slots are a little tight there we go we're going to use we're going to get the cheap ps2 keyboard and a couple people have asked me about this i got this from amazon just search for mini ps2 keyboard they have this in black they have it in white it's very inexpensive it totally works with everything so i have the adapter on here we'll plug this into the keyboard port which hopefully isn't messed up because of like corrosion or something i didn't really test that let's turn this back on again let's see what happens it initialized the video card just like that and there it is counting up the memory so i'm going to hit escape or yes escape delete escape delete delete to go into bios setup now i have to wonder what exactly kept this thing from working that first time maybe a dodgy connection for the video card that's quite possible this thing has cmos setup and diagnostic on it let's just check out the diagnostics keyboard diagnostic video diagnostic you know what there's nothing useful in here we don't need diagnostics i know the keyboard works i know the video card works that is not helpful now one thing it was counting up the memory pretty slowly and i bet you there's a turbo switch on here it's right here and i'm gonna stick a jumper on there because it probably had a switch that isn't of course not installed because whatever case this was in is long gone so this thing's probably running at a relatively slow speed without the jumper on there so we'll hit f1 to go to the setup and we're gonna go to cmos setup and there it is we basically have nothing much in here to look at primary display we're going to set the primary display to vga we'll just set the keyboard to not installed we're going to leave everything else set up to not installed because this card does not require anything set up in the bios for it to boot so we're gonna save this setup and hit enter let's see what happens okay so maybe this switch oh you know what putting that on putting the jumper on slowed it down because it counted up memory faster when i pulled that off there it is there's the ami bios 286 vga 1989 it is booting let's see what happens now we'll test this in a second but i think that that initial frozen at 30 on the postcode was because the vga card had like a dodgy connection inside in that slot that's probably what happened it is sitting here not doing anything after it did the high mem test uh that could indicate this is a problem with this motherboard oh the cpu is very warm but that's pretty normal for early 286's chipset on the other hand is okay so this froze up i'm going to hit ctrl delete and it did reboot and i think i have some stuff in the auto exec to like try to load some drivers and stuff that probably do not work on a 286. so since this is 622 i will just hold down the shift key which is what i'm doing there it'll bypass all of the startup stuff there it is the system is running we can run the old speed test here see how fast the computer is running and there it is 18 megahertz which indicates to me that this is running at zero weight states if it ran at one weight state which is what the original ibm pc ran at i'm going to unplug the speaker again uh it would be running at what like around 12 megahertz which is around what the clock speed is on this thing let's install the turbo jumper again okay it dropped down to 12 megahertz which i assume is the same as eight megahertz with zero weight states but definitely slows down a little bit with the turbo um jumper installed okay system is working cool i'm going to turn this off for a second and let's pull out the hard drive or the xt ide and let's pull out the video card because i have a feeling if i turn this thing back on we're going to get stuck at that same postcode of 30. and if i had the speaker hooks up we'd be hearing that same beep code i think yeah like i said i think what was going on and i've had that happen before it's just like the slots are a little dirty yeah there it is it's stuck at 30. that just tells me that there's not like a fault on the motherboard it's just that this video card had a bad connection obviously we can tell the keyboard is working because i was typing and it was working sometimes the battery damage can cause issues in that regard uh i think the video card is not initializing again it's doing that thing the postcode it says 1a and it's stuck at 30. i wonder if the slot that i put it in doesn't work that well let's flip this cable over and plug it into the next slot over there we go let's try this slot here this is why postcodes are very valuable yep it's working it's posting now and i could tell that even before looking at the screen because it didn't stop on one a which is the beep codes thing it went right to one um nine or i don't know went to a different postcode i probably stopped that but then of course looking at the screen i could see it initialized and now it is booting there it is those lines are nothing to do with the machine that's just the video card interfacing with the scan converter in fact if i change the profile to the correct one there we go there are no more lines that it was just a setting thing i was using that with an amiga recently and that's why it was messed up and there's all the information about this machine i bet you if i run let's try testing the system board i have no idea if this test actually does anything useful i don't think it does but but it ran and it passed anyway so yeah there we go we already know this machine runs around 12 megahertz with zero weight state so it's pretty good performance this should be a substantial improvement in speed over like an xt which there it is eight times faster than an xt for both the math and the cpu speed that's of course without the math coprocessor and that is the beauty of zero eight state memory you may have noticed when i powered it off and took these cards out for that quick testing that the bios didn't actually get erased even though there's no battery installed in here and that is because that chip which i think is this one right here that actually holds the bios settings it's also the clock chip it basically is able to retain its information for quite a while after power up that maybe there's some capacitance going on in there but i found that it's it's pretty resilient and i think it's very low power and maybe that's got something to do with it now if i wanted to hook a battery back up to this board this does output five volts while the machine is powered up because it charged up the nicad battery and with a three point whatever volt battery that was on a 3.6 5 volts is an appropriate charging voltage you do not want to hook up like a cr2032 or something that's not rechargeable directly to these pins without putting a diode and i recommend like a schottky diode because it has less of a voltage drop generally these boards work perfectly well with a cr2032 which is like around a three volt battery or so they'll last for a good long time without any issues whatsoever some boards though they don't work super great and that's because there's dropper resistors and things like that what you can do is go on amazon and buy a cordless phone nickel metal hydride battery 3.6 volts and hook that up to the plus and minus it will work perfectly beware it will leak eventually i mean it's going to take years and years and years to do that but if you have a machine like this that you work that you use regularly then that just putting another nycat in here is a good choice now you could just buy another varta like that was on here originally and maybe put it somewhere else put terminals on here like i did and run the wires to somewhere else in the case maybe put it in a little plastic container so when it does leak it doesn't just dump its contents onto the motherboard and destroy it these are my recommendations of course you can do whatever you want let's run a game on this thing as sort of a test and this is thexter which should work perfectly now it does have pc speaker audio which we're not airing because i unplugged the speaker but there it is it's running i think it's going to work i'm just going to let this sit here and run through the demo for a long time which kind of will test out the memory and whatnot there's the game actually running all right the machine has been running this extra demo for a good 40 minutes while i was waiting of course i was actually doing some other stuff but i heated up my hot glue gun and i glued down that little barge wire that one long botched wire that i had installed there so it's not flapping around in the breeze so to speak but as you can see it's running the demo with no problem hasn't crashed nothing is wrong this board seems to be somewhat reliable oh did i speak too soon i have a feeling that is the um the video card it's just a bit flaky in the socket and i have to say i've had issues with this particular card before in certain motherboards like it just it doesn't make good contact let's see if i wiggle it yeah look the computer went off it is absolutely this video card and it's i don't know what it is about this card um i mean is it thinner than it should be i don't really know but obviously if this were screwed into a case it would not be flaky it's just because the card is flopping around in the breeze so to speak but there we go the computer boots right up no issues whatsoever so this motherboard is working now of course the way i went about repairing it with these little barge wires and little pieces and it was all very silly there are many different ways to do this type of repair basically all you need to do is just figure out which traces are broken and then bodge them up somehow whether you do it on the back with badge wires or you do it on the front like i did it's totally up to you all that sanding i did you don't really need to do that either i mean obviously for a longevity perspective you probably want to do that but i've repaired other motherboards and this was years ago where i just sort of scraped enough away to tell that it was working or not and put some nail polish on it and it's worked i'm sure there's going to be lots of comments about better ways of doing this and uh yeah if you're repairing a board like this read my comment section and see what other people have to say and then decide for yourself but either way this board which was completely unknown whether it worked works so that's kind of exciting i like 286 boards i have a couple other ones i've repaired but i have another one for the future when these things are as rare as hen teeth um i have a working board so that's kind of cool so if you like this video thumbs up if you didn't you know what to do all the usual stuff don't forget to check out my second channel there's some fun and interesting stuff over there and uh get less views over there so i assume maybe there's not as much penetration of the channel so be kind of fun if uh you go over there and hit that subscribe button but anyways thanks to my patrons their names just come off the side of the screen if you want to become a patreon you can do so at the link in the description below i'd love to hear your comments about this repair though so go ahead and put those down in the comment section below and i guess that is going to be that so stay healthy stay safe and i will see you next time bye [Music] if you can believe it i finally cut my hair

Channel: Adrian's Digital Basement

Views: 60,441

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Id: JMhdANO8AMo

Length: 49min 28sec (2968 seconds)

Published: Sat Jul 16 2022