RTX 3090 Ti SLI: Bad Idea or Worst Idea?

what's up guys so a couple days ago i posted a video on this graphics card right here the msi supreme x rtx 3090ti graphics card which costs twenty two hundred dollars it's a massive 13 inch long four-slot graphics card with a 480 watt tgp it's pretty absurd in just about every respect check out my full review on this graphics card for a little bit more on that and some of the benchmark numbers but on launch day i thought to myself how could we go even a little bit above and beyond that make things a little bit more absurd and you might note that there is a special connector right here that is for two-way sli support and while multi-gpu configurations have largely fallen out of style and are not nearly as well supported as they used to be the rtx 3090 and 3090ti do support it they're the only cards from the 30 series that do i have an sli bridge right here so all i would need is another rtx 390 ti to test out that configuration and hey look what i have right here this is the game rock rtx 3090 ti from pallet i'm going to be using this card for my updated how to build a pc series in april but for now i've got both of these so should be pretty easy to just install them both and try out an sli configuration right maybe not excellent today's video was brought to you by the corsair k70 rgb pro mechanical gaming keyboard powered by axon processing technology and genuine cherry mx mechanical switches this board packs its aluminum frame with features like dynamic perky rgb lighting a detachable usb type-c cable durable pbt double shot keycaps and iq software support on both pc and mac os you also get dedicated media keys a multi-function volume roller on-board storage for up to 50 profiles and more so for further details on the corsair k70 rgb pro click the sponsor link in the video description so here's the test bed we're going to be using today this is the asus rog strix z690 maximus hero i got the intel 12900k installed right here and i also want to point out that at this point we have not gotten the configuration up and running so this might just be a fail video where we try and it doesn't actually work i did attempt to validate yesterday that the 3090ti sli even works nvidia has confirmed that yes it is supported with the current driver and in fact there's at least one other person the infamous tony who has posted some port royal 3dmark scores so i have a lot to get to but let me quickly talk about why i'm using this configuration and why i had to go through a bit of troubleshooting or figuring stuff out before we settled on it in order to run sli you need an sli bridge the newer sli bridges for the 30 series are nv link sli bridges they're unique to the 30 series and they're not even compatible with the 20 series which had a different connector that was used briefly just for that generation now because signal integrity is very important they only make four slot versions of this bridge and as you can probably see they are rigid so the cards need to be spaced out just that amount that means if you want the graphics card plugged into the motherboard with the sli bridge here on top but it means your second card needs to be plugged in right here with a four slot space and this motherboard does not have four slot spacing it has three slot spacing which seemed like a pretty reasonable thing in the past but that was before these 3090s came out with their ridiculous tdps power draw and massive coolers so from there the question becomes is there an lga 1700 motherboard z690 ideally that can support the 12900k and also has that four slot spacing and the answer is yes there's the big brother version of this motherboard the maximus z690 extreme versus the hero that we're using today that has four slot spacing it's also an 1100 motherboard and while asus was willing to send me one over they weren't able to get it to me in time to do this video today but i might be taking a look at that board in the future there's also a couple z690 motherboards from evga that have that four slot spacing somehow they were aware that that might be necessary but those boards are pretty difficult to find at retail right now and i sort of ran out of time yesterday so i decided let's go with plan b and plan b was to nicely ask joe my editor to run over to microcenter and pick up a couple of these these are pcie 4.0 rated by 16 riser cables and that will allow us to use this motherboard just positioning the graphics cards up above we're going to need to create some sort of bracket or support to hold them in place and i almost forgot the real reason we couldn't go with the maximus z690 extreme or those evga boards was because i finally pulled this card out of the box and positioned the pallet game rock next to the supreme x from msi and lo and behold the sli connectors do not line up at all so i could not physically have them in a motherboard even with proper four slot spacing and use both of these cards together you would need to use the exact same card or at least one with the exact same pcb configuration in order for that to work and since msi didn't have another supreme x that i could borrow temporarily to do this configuration we were left with only one choice and that's to go with what we're doing today and using these riser cables to hopefully get the configuration up and running so with that decided yesterday evening i got to work doing a bit of tear down with the test bed i used to test the supreme x which is an amd platform the x570 and i tested with the 5900x and then swapping some parts over onto this testbed which is a little bit more open and should hopefully give us a little bit more freedom to create some sort of strange structure above to hold the graphics cards while we run these tests so right now we're running windows updates just getting this testbed back up to speed and here's a quick look at our riser cable so this is not going to be ideal testing that we're doing today because uh the riser cable does add a little bit of latency you're going to get very very slightly less performance with the riser cable than you're going to get being plugged in directly to the motherboard this is just 200 millimeter riser and i guess it's compatible with most of the liam lee cases and it was also one of the only ones of these that were able to source and get in time to shoot this video today because today is really the only day i have to do this also i am by no means an expert overclocker i've dabbled in it occasionally i do like overclocking but i do not have the diligence the patience the attention to detail to get to the point that a lot of professional overclockers do out there all that is to say we're just trying to get this up and running today i through my career over the past i don't know 10 12 14 years have at different times gotten access to really high-end gaming graphics cards pretty early in their launch cycle and one of the things i've always enjoyed doing is plugging them in seeing what sort of that peak performance is with the new series and also maybe getting my name up on the 3dmark leaderboards at least for a brief period of time until the real overclockers get their hands on them and push them much much further than i ever will and here it is my glorious configuration my support system for the graphics cards built meticulously and with much care using my daughter's plastic building blocks they're so colorful meanwhile as you can see even though the sli fingers are offset on these two cards we were able to position them in this way still allowing a bit of airflow from underneath obviously this structure had to be reinforced down here to provide the maximum amount of safety and security for the cards above there since this is i don't know 4 400 ish dollars worth of graphics card right there i do want to point out that i strategically used some 2.5 inch ssds down there for spacers just to get some extra support over on this side and i also added some cardboard insulation anywhere where there was like heat fins or whatever that might be directly in contact with these plastic blocks because i'd like them not to melt if we could avoid that finally we have both of our three-way 12 vh power connectors here plugged in and those are all routed over to our 1600 watt power supply which should be enough for this configuration but depending on how far we get this afternoon and whether or not i want to take any more attempts at this i may or may not set up a second power supply to power the second card independently for now though this is the moment of truth i really hope this works because it would suck if it doesn't yep both cards have lit up that's a good sign i think we're up and running now let's see if sli works we are in windows the nvidia driver has been installed and in the control panel we can see our two rtx 3090 ti's glorious let's go and configure all this nonsense because we need sli where's my sli shouldn't that be right here span physics no i can't just use one as a physics processor all right i might need to restart because the adapter might not be plugged in so sli is not just working right off the bat there's a few potential reasons why this might be happening one is that the sli bridge isn't making contact i double checked that but it seems to be okay now i'm using gpuz just to double check the stats on this card of course the high level stats should all be the same using the same ga 102 gpu die size and all that should be exactly the same they might be using different bios versions because we have one bios from a palette card and then we have a different bios version here for the msi card in my experience that doesn't cause sli to not function though there's a few different things we could do here we could try to set the same v bios on both cards that would be one option or we could try swapping the cards to see if the msi card and the number one slot pellet cart and the two slot fixes the problem just magically so i decided to do that v bios update and i decided to update the msi card because i've already tested this card so in a worst case scenario um you know i i can figure things out with this card and hopefully the game rock card should still work in its default configuration as i go through testing that the flash was successful you can now see that uh gpuz thinks this is a palette card and the gpu clock speeds and everything are reflecting that as well however you might be able to tell that uh we are getting screen dropouts like regularly so that's that's not really a good thing so i think it's pretty evident at this point that the msi card did not accept the pallet v bios with much grace at all we're getting random sort of screen dropouts and stuff just like what happened there again now i was hoping that by swapping the palette card to the number one slot we might bypass this but you know we're taking shots in the dark trend to diagnose these issues as we go and unfortunately we're burning a lot of time trying the different configurations as well but i have one more thing that i'm going to give a shot and that is to try the msi v bios on both cards um see see what happens then this is a little disappointing after the work we have done today rebooted yet again after flashing both bios's over to the msi v bios and we now have the same situation pretty much configure sli surrounding physics is what it should show here but it's just showing us surrounding physics and we can confirm with gpu-z that our top card is uh displaying the msi v-bios and the bottom card is also on that same v-bios so why doesn't sli work if i know now it's possible all this uh messing around i've done with the v-bios wasn't even the main issue in the first place like i said i've worked with cards from different manufacturers before as long as it's the same gpu inside it shouldn't matter if they're running different v-bioses and typically it will default to whatever the top cards clock speeds and everything are running at it's possible that the system just really doesn't like my pcie riser cables it's possible that because we built sort of a support structure out of blocks and set these on top of it and it's a little bit wobbly and probably not lined up exactly the way it is we're not getting good contact with our sli bridge on the plus side though at least we haven't bricked any of these cards yet oh except maybe we have it's not a bad joke but i am sort of at a loss for what to do next so uh give me a moment to think let's see if i can figure something out it was at this point that i started to second guess my idea to quickly toss my rtx 390 tis into sli to try to easily climb my way up the 3dmark port royal leaderboard however i did come back to it the next day i had spent some time online looking up some 3090 sli troubleshooting tips because there's nothing for 3090 ti at this point so i came back to it thinking maybe one of these will work and we can move ahead the first was to check the pci express connection status and you can do that in the nvidia control panel all you have to do is click system information down in the lower left you should be able to see both of your cards there if they're both being recognized properly and if you scroll down in the details panel there should be a bus listing which for me was pci express by 8 gen 4 for both cards which is exactly what it should be if there was a mismatch there then the nvidia driver definitely would not allow me to enable sli however they both lined up so that didn't seem to be the issue however i did want to double check that my m.2 ssd wasn't installed in a slot that was somehow stealing lanes even if it's still being recognized properly by the nvidia software but as it turns out my m.2 drive was installed in the top slot of the maximus z690 hero motherboard that one has its own four dedicated pcie lanes so that clearly could not be the problem the next step was to drive some driver reinstalls of course you can always clean install and the best way is to restart the system while holding down the left shift key that will give you advanced startup options as a reboot option and from there it should give you a list including option number four which is to boot into safe mode once into safe mode you can use ddu or display driver uninstaller which you should download before you reboot into safe mode by the way that will completely wipe the drivers then restart the system and you can attempt a clean install when i first installed the drivers i only had a single graphics card installed and then i added the second one while the system was shut down but one of the troubleshooting tips was if you did that attempt a clean install of the driver with both cards installed set up with the sli bridge in place and everything good to go but guess what that didn't work either so went on to another long shot which was a recommendation a couple people made that said plug your display connector like your display port or your hdmi connector into the secondary card and your sli setup get a video out from that card then switch it back to the first card and then magically sli should work that did not work either so it's getting a little desperate at this point i hadn't heard back from nvidia but i knew as i think i mentioned earlier that 30 90 ti sli should work because there are legitimate 3d mark port royal leaderboard scores with that setup that have gone up in the past 24 to 72 hours depending on at what point in this whole project i was looking at it so i decided to look at those results a little bit closer we have one from tony and another from chris masani from evga and the one thing i noticed about both of these is that they were running 64-bit windows 10. it also seems like they were using the right configuration like this one was an rg max z690 extreme which has four slot spacing and likely also using identical models of asus graphics cards and even the evga guy was using a maximus z690 extreme in order to get the 12 900k to work and presumably matching evga rtx 3090tis but like i said windows 10 was the other similarity between them all of my tests so far have been on windows 11. so i grabbed a new ssd popped it in did a fresh install of windows 10 did some driver updates fired up the nvidia control panel and now no and it didn't work yet again so i was all out of time on this second day attempting to get 3090 ti sli to work that was last week though this week we are starting fresh and i got a response from nvidia unfortunately their best suggestion was that the sli bridge maybe wasn't in alignment because i sent them a picture that i posted on twitter of this sort of haphazard configuration so attempting to fix that if it was the issue i took the sli bridge and put it upside down on my desk here and then mounted the graphics cards upside down to it using it as sort of the focal point of the build i supported them in various ways with some post-it notes and things i got some blocks of wood and i used gaff tape and i basically made a monstrosity that was kind of holding both of the cards together in roughly the same position that i could sort of lift up and move and you know it was fun that's like one of the whole points of doing a video like this is just to sort of see if i can get something to work so after much struggle yet again i took the monstrosity i had created inverted it plopped it back onto my test bed setup plugged the sli bridges back in properly connected back up the pci express power cables fired up the system went to the nvidia control panel and it still didn't work so like i said i was getting to the point where i was thinking this is no longer going to be a paul sets up and tries out 3090 ti video this is going to be a fail video about me trying everything i could think of and then it never working but that's one thing about troubleshooting that i have learned over the years is you might come to what seems like an impasse you hit a wall a stopping point where you're like i can't figure this out but oftentimes it just takes a night's sleep or to step away from it and come back to eat some food maybe i've done that before where it's like oh i forgot to eat and now my brain doesn't work but if you have the luxury of a little bit more time you can often think of just one more thing to try and my very final attempt at getting this to work for this video was to swap the test bed out completely finally i'm like enough the 12 900k not gonna work here even though it's the ideal cpu to use let's just see if getting rid of that part of the setup completely and then just swapping in my x570 testbed which is an msi x570 meg ace motherboard still the same corsair ax1600i power supply still the same cooler and all but that doesn't matter it's a very similar setup except it's amd now and it has the 5900x not even the best cpu to use in this scenario because i'd rather have a 5950x in there fortunately after unplugging the riser cables and the power cables it was just a matter of pulling the test bed out and leaving the graphics cards here and setting the new testbed back in there fired up windows it's already got windows 10 on it and it's good to go this is the test bed that i ran my 30 90 ti initial benchmarks on for launch day but i kind of forgot that and i thought i think i still need to update the driver and here's what happened i'm pretty sure i need to do a driver update here but one sec oh i got 512.6 the hell the hell is that oh my god oh my god it's working holy it's working okay oh my sweet merciful gaben it's functional and i can actually run a benchmark of course i don't want to get too far ahead of myself i have not actually ran a benchmark with this functional system working yet i'm going to save that for you guys right now so let's load up steam and i should also point out again i am like out of time i need to leave very soon to go and pick up my daughter at the end of the day today so so i'm just going to run one test and i'm going to see how much further up the leaderboard i can move i'm literally in 100th place right now i've fallen that far from when we did the rip j rip gn and stuff however long ago that was should i participate in this this just popped up i mean i mean i guess i'll be in verified company sure why not yes i like to participate in the survey go ahead and send all right there's my gpus recognized by 3dmark load up the port royal and let's just hit run so let's head around see what happens here you know fire it up i'm pretty sure both cards are still running the msi supreme v-bios if i recall correctly so that should possibly apply a little bit of an overclock to the game rock card there so the system was pulling uh around 1200 watts 11 to 1200 watts which uh isn't enough to trip the breaker but it was enough to trip my power strip down there i also have other things turned on so what i'm going to do right now is turn as much stuff off as i can just so i can try to get through one pass with this and i'll just i'll just record manually with handheld cameras on battery iron up the port royal again here she goes about 1 50ish 11 50ish they're kicking out a lot of heat now it's getting warmer here's the end what do we get what do we get what do we get oh 27 620 i don't remember i don't remember what my other score was oh it's validating hey valid score we got a valid score boom oh and i got an achievement that's what this is all about light speed the light speed achievement that's a goal see that's a that's success and that shows why i spent all the time doing this so with that score of 27 620 with fully functional rtx 3090 tis and sli what what happened how did i oh yeah my so the score i already had was 28 363 so obviously you know i was overclocking there and i was you know piping cold air at the cards i was doing a bunch of other stuff too and i'm not trying to recreate that with this video by the way like i said it was just like i've got these cards i'm compelled to plug them in together and just see if i can get a score so here's what i'm going to do my schedule this week is a little weird and i don't think i can post this video until a few days from now so i'm going to plug away at this maybe a little bit later tonight when it's cooled off a little bit give myself a little bit more time to do some overclocking and maybe right now i'll be posting a better score that has moved me up the leaderboard maybe just a little bit hoping to be 28 363. oh i did it i did it 29 579. i win i mean i beat myself i beat myself real good never mind never mind all that i have come back with just a very very little bit of time on the final day and done some final configuration setups with the 5950x installed right here got some g-skill trident royal z rgb memory here that's 4400 speed rated but i'm actually running it at 3 900 speed so the infinity fabric can run at a reasonable speed too now let me let me turn the fans down okay that's much quieter i i must stress that this was literally like a five minute overclock that i did this morning just because i had a little window of time to get this done but you might have seen a moment ago we came out with a port royal score of 29 579. i'm not even upping the power limit i just threw on a quick core overclock and a memory overclock and the gpu is running at about 2190 2190 megahertz on the first card and 2130 2000 right around there for the second card temperatures did start to climb up there actually the number two car got quite warm and that's probably what was keeping the frequencies down i also had my ac pumping and stuff like that but the point i'm trying to get out here is that i have accomplished my goal of breaking my record before and keeping myself on the top 100 leaderboard in port royal at least for the time being and maybe just maybe i might have reason to come back to this little project i can't tell you guys exactly why but i have some hardware that's arrived just recently that i can't share with you quite yet and maybe i should try this configuration out with that if you guys think that i should do that then definitely hit the thumbs up button let me know in the comments section down below like i hopefully said from the get-go when starting this video this was just sort of a flight of fancy me trying to do what i could with these graphics cards since i have them and i'm happy that after a bit of struggle i got it functional and managed to get a bit of a result there i am in spot 1000 with my 28 000 score how much am i gonna move up here oh there we go jumped up to spot number 43. super happy with that and while jay still has a number six score up here with all of his ln2 overclocking efforts with the 3092a sli i have at least jumped ahead of steve and the crew at gamers nexus who is now in position number 54 but that's not really the point of all this the point was just you know to see what i could do and i did what i did so there's the score but that's all for this one guys like i said if you got comments for me suggestions for round two of this if i should even attempt it leave those in the comments section down below don't forget to subscribe if you're not already check out my store at paul's hardware dot net for shirts mugs paint glasses and paul's hardware merch i really really can't reiterate enough just how happy i am that this wasn't a complete waste of time or an exercise in failure but thanks again guys and we'll see you all in the next video

Channel: Paul's Hardware

Views: 139,066

Keywords: computer, PC, PC gaming, personal computer, computer hardware, paulshardware, rtx 3090 ti sli, rtx 3090 ti, SLI, 2-way, rtx 3090 ti 2-way sli, nvlink, sli bridge, 4-slot, 3-slot, spacing, troubleshooting, vbios, driver, ddu, how to sli rtx 3090, 3dmark, port royal

Id: yyGpbiORR3M

Length: 24min 52sec (1492 seconds)

Published: Thu Apr 07 2022