not entirely correct. it still requires driver support nvidia’s blog says this very clearly.
the API cannot change how it uses the GPU’s or if the cards are linked or not. Cant say for AMD their cards are worthless because of their drivers so who knows how this works.
then clearly, Nvidia drivers support it if it’s working on the latest 457.51 drivers as shown in the screenshot above… or here’s a repost of the screenshot showing two different manufacturer 3090 cards being utilized without a hardware NVLink bridge in WoW:
oh they do, i wanna say they added it a year ago but dont quote me on that. The real problem is wow’s dx12 implementation sucks. i lose over 40% performance when switching from dx11 to dx12 and i dont have a low end system either. No other DX12 game murders my framerate so much. Your framerate would likely be higher in dx11 than it would be in dx12 if you had sli supported cards. the less than 50% usage on both cards show how poorly wow is optimized
I saw no performance difference choosing between dx11 and dx12 when i was actively testing this feature with 30 series cards… This performance loss may be true with older cards which were not optimized with the latest dx12 hardware/features, for example a native DX11 card (i.e. a GTX 900 series card or the known poorly optimized 10 series cards) running DX12, but as of today with modern 30 series cards which are native and optimized for DX12.1 Ultimate, there is little to negligible (if any) performance difference between DX11 and DX12.
Lastly the less than 50% usage on both cards is the fact that i am literally using dual RTX 3090s in that screenshot. Quite literally the game can’t even begin to push the performance of one of them yet alone two of them… that and also i’m quite confident the 5000 series Ryzen CPU is the bottleneck of the performance of my system by that point.
the game cant because of the sloppily done DX12 addition. i got a 9900K at 5.2GHz, 32GB 3600MHz ram and an rtx 2080 Ti and in places with more than 10 players my framerate tanks from 230+ to 50~ in DX12 and in DX11 it never drops below 90 even in raids/dungeons with lots of effects on screen.
you dont know how it works i dont think. it isnt the game not being able to push the cards, it’s wow being horribly optimized paired with a poorly slapped together DX12 implementation. Depending on the exact 5000 cpu it might be the fastest cpu on the market period.
poorly optimized or not, performance has a way to brute force it’s way (i.e. with an RTX 3090 >.>) to the point that you don’t notice any performance loss due to any Blizzard’s poor optimization of DX12, especially when the game’s framerate is consistently over (or locked to) your monitor’s refresh rate regardless if there’s 1 or 50+people in the area (i.e. Oribos).
what? that makes no sense at all. your performance should be the same regardless of the API, what limits it is not adding it correctly which from what i keep hearing wow did not. it makes too many draw calls for no reason crippling performance hence the overwhelming majority of people saying what im saying. DX11 runs smoother and gives a higher framerate.
i got a 240Hz monitor so i do notice a significant difference between 90 and 50 its like going from 30 to 60 its huge. oirbos actually runs smoothest for some reason idk why.
well, it’s getting to the point of being pointless to counter you, as even with evidence, such as screenshots, a framerate improvement of up to 100% (i.e. from 70fps to 140fps when one 3070 vs two 3070s), and first hand experience with two of the latest highest performing graphic cards (dual RTX 3090s), you still feel the need to attempt to disagree with everything 
It is clear that no evidence or other’s first hand experience with the contrary is going to change your beliefs.
Unless something relevant is posted to respond to, this is where i leave this topic thread as mentioned above, I have no more use for or interest in this topic as I achieved the goal I originally set out in the OP when I finally got my hands on a 3090 as opposed to being stuck with a 3070 when this topic was created.
P.S. Whether if Blizzard implemented DX12 good or not is besides the point and serves zero relevance to this topic, as regardless of how Poorly implemented DX12 is in WoW, there was still a performance uplift of up to anywhere up to 100% with dual cards vs one (as noted in the OP) and no noticeable difference when setting to DX11 (legacy), DX11, or DX12 modes in WoW as noted with the 30 series cards.
Thus, as far as we know, the framerate increase you mention that is experienced when setting DX11 instead of DX12 with your older card may solely be due to the hardware optimization of the 10 or 20 series cards with DX12… Take the 10 series, just google it, this is well known that these were poorly optimized for DX12 regardless of having hardware level DX12 support, and one can expect this optimization and performance to improve on a hardware level with each new iteration of graphic card (to the 20 and to the 30 series).
because your evidence is anecdotal. you cant just benchmark 1 system and proclaim all of them just be the same, thats not how it works. The whole point of DX12 was to remove all bottlenecks from your system by granting the api direct low level hardware access. the fact wow runs worse proves they did a lousy job adding it.
anyway im not arguing anymore. live in ignorance if you like, that on you.
Which will work until there is a bad driver update and then it’s a big PITA.
Explicit Multi-Adapter typically requires a setting to be selected in order for it to be enabled. Searching throughout the settings list in Retail, this option is not visible. Is there a config setting in the Beta that would enable this? It may simply be a buried feature
no setting required. it’s just a baked in feature to direct x 12 ultimate.
Only toggle i’d imagine is on the back end developer side, for the developers to add the support to their game or not.
unfortunately blizzard didn’t carry over the support from shadowlands beta and pre-patch into retail for launch, as it didn’t work in the retail build, but still worked in the beta build at the time as mentioned in the second half of the reply here: Explicit Multi-GPU Support added to Shadowlands! - #77 by Ravens-sargeras
color me suprised.
i thought sli died with that batman game lol
call it pride but i got through everything post WOD on a 970 ftw edition by evga. also i told myself even though i should have upgraded ages ago i would stick it out until it died. call me sentimental but its my first build. believe it or not i hated computers growing up. i was solely console until 2008. in 2009 my grandpa taught me how to build a pc. ive upgraded everything minus the board and psu. yes its a ddr2 system. anyway a few weeks ago it just died. i was waiting for it. i assumed it was the psu or mobo but i did some diagnosing and it turns out the pcie power connectors are shot on the gpu. i ordered a custom build minus the gpu cause i was going to use the 970. got a pair of 1070s now. waiting on my build to get here.
with the chip shortage beggars cant be choosers. i just snagged a pair of nvidia 1070 FE’s both for 325. either way it gives me some breathing room for a bit
Just remember that SLI will only work properly when you run the game in DirectX 11. Using DirectX 12 will result in only one GPU being used.
Odd to hear about your 970. I don’t think I’ve ever had a card die that way. Was the connector loose or something?
I’m running a 5600G and a full 50 player party at Antros doesn’t drop a single frame. Bad raid performance is caused by poor CPU performance. Low thread counts, bad memory configurations, older architectures with 5 layers of security band-aids, these are the woes to watch for.
That’s because NVidia abandoned SLI. To be honest, SLI was somewhat of a gimmick feature anyways. It almost never resulted in a significant performance increase that actually justified buying two GPUs.
1 Like
While it’s true that SLI has been depreciated, it doesn’t mean that it doesn’t still work in certain situations. If you are using older cards, playing the game in DirectX 11, and that game has a SLI profile (which WoW does), then it will still work. Even if the game does not have an SLI profile, as long as it supports DirectX 11, you can still configure SLI manually.
That is simply incorrect. WoW has always had great support for traditional Multi-GPU (DirectX 11 and prior). I’ve run dual and quad-crossfire setups in the past. Even with quad-crossfire, it was able to make use of all 4 GPUs. My backup system still uses 3-way SLI. I had started with a single GTX 680, then got a 2nd card, and eventually got a 3rd card. Even going from 2 cards to 3 cards showed a noticeable increase. I just finished testing that 3-way SLI setup with the Dragonflight pre-patch. I can confirm that DirectX 11 SLI still works great with WoW, making use of all three GPUs.
The main reason why WoW didn’t always show gains from SLI is the same exact reason why it doesn’t always show great gains when you do something like drop a RTX 4090 into your system… It’s because WoW is generally more CPU limited than GPU limited. If you are CPU limited and you increase your GPU power, your performance will remain the same because you didn’t actually fix the bottleneck that was hindering your performance. BUT, once the CPU isn’t the bottleneck anymore, WoW is absolutely in a position to take advantage of that extra GPU performance, from a single fast card or from SLI using older cards.
I certainly would not recommend SLI at this point if you are setting up a new system, but if you are still using older hardware and it supports SLI, there is no reason not to still use it. It can still make for some cheap and interesting upgrade options on the lower-end of the spectrum also. For example I have a friend who was still milking his GTX 780 Ti. A great card for it’s day but obviously showing it’s age at this point. New GPUs still have somewhat inflated prices from the crypto BS, so he simply didn’t have the money to get a faster GPU. Well, I was able to score a matching 780 Ti for him on eBay for $45 and it resulted in a significant and noticeable performance increase. In that case it was absolutely worth every dollar.
I’m not talking about WoW. I’m talking about SLI in general. There is a reason why they abandoned it.