Extreme Overclocking a Vintage Mac with Spicy O'Clock!

i love spicy things mmm ghost pepper which is why today we're taking our power mystic color classic and we're gonna make it extra spicy because who doesn't love a spicy apple actually that was surprisingly good thanks whiteboard guy anyway we're gonna see just how far we can push an overclock on this power pc mystic using an incredible new device called the spicy o'clock i bet that opening skit makes sense now huh so stay tuned [Music] and if you enjoy going to extreme lengths to squeeze out every last megahertz from your classic computers i hope you'll consider subscribing to the channel we do a lot of questionable electronic engineering and uh food preparation around here so it's definitely worth sticking around so this is the spicy o'clock it's a genius little device from our friend k koba which replaces a 68040's crystal clock oscillator with an adjustable silicon one to understand what this thing is going to do i think it's worth talking about how enthusiasts overclocked these macs back in the day a good number of 030 and o40 max have their clock speed set by crystal oscillator chips and to change the clock speed all you need to do is swap out the oscillator for one with a different value by trial and erroring your way through a pile of oscillator chips you could find the highest speed that your particular board would run at well spicy o'clock removes the need for you to have a bunch of oscillator chips lying around and instead lets you just try different frequencies so you can tiptoe your way right up to the line of what your board can tolerate and thank you k koba for creating yet another bit of magical macintosh invention now here's where things get really special in our mystic here on the motherboard we have a power pc 601 upgrade card running at 66 megahertz but that clock speed is tied to the clock speed of the 68040 processor on the motherboard so when we overclock the motherboard here the power pc chip should also be overclocked and uh yeah should run double the 68040 speed well theoretically i don't think anyone has actually tried this in a mystic before you know what's not theoretical the sponsor of today's video pcb way did you know that pcb way recently moved to a new factory now with improved production capacity and efficiency great pricing is even better from august 5th 2022 enjoy a 20 discount on four and six layer pcbs pcb way is a one-stop shop for pcb prototyping and production as well as all kinds of different prototyping and manufacturing so thank you pcbway for being a long time sponsor of this channel and here's to continued success in your beautiful new location let's take a look at the stock gaming performance of the 68040 and then we'll take a quick look at the power pc's gaming performance and uh see how much of an improvement we get and of course we're starting with my favorite wolfenstein 3d which on the stock color classic is absolutely unplayable but on the mystic 68040 is uh well it's not perfect but it's pretty nice and yes i'm a weirdo i play with the trackball and uh i think it's pretty awesome that way we could try a little 68k duke nukem 3d as well alright so at a small size it's uh it's playable and this is the size that i've been playing it on the color classic yeah this is the size that i want to play the game at and uh honestly i mean it's not that bad but it's not great oh my god i can't even play uh with multiple enemies on the screen it is unplayable wow all right so let's restart into the power pc upgrade and try out some power pc only games which is pretty incredible on the color classic we can only just play carmageddon but we can play it yeah look at that carmageddon on a macintosh color classic all right meme street hang on to your helmet i believe that's a double entendre oh the sound is weird the frame rate is uh i'd say about five [Music] file driver bonus oh no i just destroyed my car uh well so this is the spicy o'clock and as you can see it's a pretty diminutive little board here with some fun silk screening on it little mac with sunglasses kind of k's trademark and well it's pretty simple there are three jumper settings to control kind of big jumps in the settings and a fine tune control here with this potentiometer and i'm just going to use this little crt tool to spin that around and then in order to figure out what the actual value is here all we need is a multimeter and we connect the two pins in the middle here set this to ohms and we can check whoops we can check what the setting is and then using a fun tool by steven arsenal we can determine what the frequency is going to be based on what we set this thing to and actually we don't even need a multimeter with that tool we can kind of approximate uh what the setting is but i'm going to do the multimeter method and i've kind of rigged up some uh little connectors here to go on these two pins so i can uh yeah not have to hold the multimeter probes a little janky but it does the job and we can see values now on the multimeter and as we twist this around the value on the multimeter will change and as we change the jumper here around the value on the multimeter will change but really what i want to do is crank it all the way up so that uh yeah we're going to start from the highest possible overclock and then work our way down from there but let me show you what i did to the board itself to hopefully accept the highest possible overclock per the wonderful video from jdw on the spicy o'clock i have used low esr panasonic oscon capacitors to recap this board which uh pay no attention to the funky looking traces there definitely did not rip pads off but never mind that if you want to see some really great overclocking in detail definitely check out jdw's video he is just a wealth of knowledge on 68k max and the other thing i did is on the upgrade card itself i have swapped out the 68 lco40 for a full 68040 processor which has an fpu and i've also put a much beefier heatsink on it compared to the heatsink that was on the original lc version of the processor and i have repasted the power pc chip which is underneath this funky looking heatsink this guy is actually going to live on this nice little mount here that k sent me 3d printed quite nice so that's going to live here and it's going to give us access through the back of the case actually to twist and fine tune the splicio clock so we can actually play with the frequency that the computer is running at while the computer is running which that'll be fun to try out okay so i have installed our spicy o'clock here and wired it in over here and i'm just going to put a bit of electrical tape here to make sure that it doesn't touch since the accelerator is going to be over top of this connection and that pin does stick up a little bit and then the other thing that i did was i tapped into five volts on the back of the board here again much like jdw did because i want to add an additional fan to the system uh since we're overclocking although i'm gonna put mine in a little bit of a different spot than he did so now we just have to put our power pc accelerator back in and the other thing that we need to do is switch out the vram so we had this stock vram in there but this is pretty slow this is 80 nanosecond and if you overclock the system too much it'll actually become too fast for this vram so there are some aftermarket solutions i have one right here which is 60 nanosecond vram by mr fahrenheit based off of the design by steven arsenault but actually even this is a little bit too slow for the most extreme overclocks so much like jdw i have this very special 60 nanosecond vram from kcoba himself and uh this is a lower latency design because it only has two chips instead of four so hopefully this will allow us to hit at least 50 megahertz alright so i have the spicy clock installed it's right here and the spinning bit is accessible from the back and i have our fan here which is going to wind up mounted about here because mr k kobo also included this nice 3d printed back panel which allows access through this little hole here to spin around that dial and i'm just going to kind of screw the fan in right here and cut this little bit out and have some airflow being pulled in the back and then exhausted out here so it's going to go over the processor accelerator card all right spicy should be set for 50 megahertz let's try and power it on no chime okay so i switched the jumper around uh to the middle position and now we are booting but i have no idea what the speed is going to be but at least we know the spicy clock does work with the system oh crap all right well according to clackometer we are now running at 40.45 megahertz we are overclocked not to the point that i want to get to but still look at that 40.45 up from 33 so i think what i want to do now since it's running is reboot into the accelerator and see if it really does run at the overclocked speed yes 81 megahertz power pc up from 66. oh that's amazing oh look at it that's that's such a huge percentage gain megahertz okay now what i want to try is actually twisting that knob with clockimeter open and uh see if we can adjust the frequency of the processor on the fly alright i gave it a few twists it has not crashed recalculate oh i twisted it the wrong way look at 79.25 all right all right i twisted it up system has not crashed 83.5 let's keep going okay so i've rebooted into 68040 mode and uh i'm slowly bringing up the speed of the processor i'm at 45.95 megahertz the goal is 50 and i'm kind of curious if perhaps the 68040 can handle 50 megahertz but the 601 power pc cannot handle more than i don't know 80 or so megahertz 47.5 we're getting close 48.6 oh it says 50. okay i tried to go a little bit past 50 and it froze okay so it didn't want to boot back up until i took it back down to like 45 megahertz and then i booted back up snuck it back up to 50 again and uh yeah i'm actually starting to see some issues there's some graphical glitches uh yeah i i don't think that this computer likes 50 megahertz and i think that's luck of the draw really okay we're now running at 48 megahertz still graphical glitches all right 46.19 let's see if we can start up at this speed okay it's booting but there's no video all right it's coming up and i have mass control all right we are currently running at 45.24 megahertz i guess 45-ish is where this computer likes to sit and that's a shame i mean it's kind of luck of the draw and uh every little detail about this board could be the culprit slowing it down i mean even that weird badge that i had to make for that capacitor maybe that is interfering with the system enough that it just prevents it from going to those very highest speeds but let's see if we can actually restart into power pc because honestly that's the most important thing to me okay well it would appear that the power pc chip is the limiting factor in this machine and i say limiting but it's not really that limited if i set it to anything above 86.25 megahertz it won't boot but i mean that is still pretty darn fast not the 100 i was hoping for and certainly not the fastest possible mystic color classic power pc but i'm happy with that okay just look at these scores with the stocko 40 being the standard mystic color classic which is already an order of magnitude faster than the stock o30 color classic the spicy 601 overclocked power pc is 297 percent the speed of this taco 40 and in floating point that's even that's even crazier let's uh zoom out a little bit yeah 1223 the floating point performance of the stock o 40 system the 33 megahertz o40 but yeah you know what we have to do we have to look at some games hang on to your helmet oh wow that started way faster oh yeah look at this that's a frame rate right there oh my god it's playable oh it's much much better it was unplayable before i'm not gonna say this is fast but it's playable look at that i don't know i'm upside down flip me back over oh this is so exciting this is worth the whole thing look at this [Applause] really you're going to leave me upside down come on all right and boot it back into 68k mode so we can check out our other two games here oh yeah well it's much much better although this game is notoriously poorly optimized i do wonder if it would still run better in power pc mode okay this is much faster this is a much better optimized game oh yeah excellent okay so this is the big test here and oh it's much much better even with all these things happening on screen at once yeah duke is playable [Applause] [Music] i mean i'm still gonna die obviously okay so that'll do it for this extreme overclocking of our power mystic color classic and thank you so much k koba and steven arsenal for making this magical spicy o'clock device and thank you kay for sending me two i mean i i paid him for him but still thank you i've wanted to build a mystic macintosh for so long since i was a teenager i've been trying to collect parts for this that lc 575 that i had that donated parts to this you know i rescued that from my mom's basement just to have this machine at this level of being upgraded is amazing and it's so versatile now in such a small package it can run 68k software natively with the overclock 68040 and it can run powerpc software natively using its now overclocked powerpc 601 processor and i can switch back and forth and i can fine tune the clock speed to get the best possible performance i can play carmageddon on this thing on this tiny beautiful trinitron screen it's just it's so cool i think the next steps for this machine well there is one more power pc upgrade that could push this even further towards the very end of daystar's existence they made a 100 megahertz accelerator for the lc 575 motherboard and after daystar went under sonnet produced it for a short time under the name sonnet presto ppc 604. i don't know why they call it 604. it's a 601 but still that upgrade is probably nearly impossible to find but i'm going to keep my eye out because that would make this the ultimate machine and i'm really curious to know can that card overclock over 100 megahertz and uh yeah because i think that card runs 3x the processor speed instead of 2x like this one so maybe this can actually be modified to do that i don't know but still can you imagine this machine with a power pc processor over 100 megahertz but that'll do it for this video if you enjoyed it i'd appreciate a thumbs up and if you'd like to see more macintosh shenanigans like this please subscribe down below and thank you very much for watching and a special thanks to alberto guiller camila noceda chris allegretta chris briggs chris calderon chris nelson cobalt retro tech control alt reese daniel hubbard greg from hrut k mods paul spencer ryan scott thompson and sutek who are my highest tiered patrons and all of my patreon supporters for helping to make these videos possible

Channel: Action Retro

Views: 41,492

Keywords: retro, vintage computers, macintosh, apple, retrocomputing, retro computers

Id: R3pizn9JFIA

Length: 22min 52sec (1372 seconds)

Published: Sat Aug 13 2022