PC Drivers & Software

[tsume]

I swapped out my 3090 for a 9070XT and was happy to see a nice 20-30% boost in FPS on my flatscreen games.  However, in VRChat I am seeing the opposite - a 30%+ performance drop compared to my 3090.  This is even in empty worlds with just me in it, using the same exact graphics settings I used with my 3090 (godlike resolution in Virtual Desktop, and ultra + 8x AA in VRChat).  I am playing via Virtual Desktop using H264+ encoding, and I don't see any issues with the encoder latency or anything.  It just seems like the 9070XT is not rendering the game as fast as my 3090 was, which is odd because the 9070XT is so much faster than my 3090 in my non-VR games.  I checked and there's still plenty of VRAM available so it's not an issue of that either.  I would have expected the 9070XT to run the game at least as good as the 3090 did based on how fast it is in non-VR games.

Is this a case like with the 7000 series where the VR performance was not quite up to par at launch?  Or is this just what I should expect from the card?

Edit:  It seems like it may just be what to expect from the card.  The 3090 has almost 50% more memory bandwidth, and at such a high resolution with MSAA enabled in VRChat, memory bandwidth is really important.  With no 9080 or 9090 this gen, I guess I'm gonna have to stick with my 3090 for another generation 😞

[Jorn]

I have tested this on a 7900XTX as well and the 7900XTX gets roughly the same performance as the 9070XT in the same scenario with the exact same settings, roughly 30% worse than the 3090 depending on the scenario. I also found a post on Meta's forum from 2023 where they demonstrated that the 4090 and 7900XTX ran similarly-ish in 2D games, yet in VR the 7900XTX ran at half the frames of the 4090.

I can't find any other cause for this terrible VR performance other than attributing this to a driver issue. It seems it has been an issue since at least 2023 and it still is now with the 9070 XT. I would love to get an official statement from AMD on why this is happening with their GPU's in VR and if we can expect it to be fixed or if it can be fixed at all.

Considering the 7900XTX has the same memory bit bus as the 3090 it's unlikely that it can be attributed to memory.

[VirtualDJ]

i speak as a person with 6000 hours of vrchat, vrchat is totally problematic with amd (unity in general). try running vrchat in the beta build and see if it improves a little (latency on my rx 6000 decreased a lot in the beta).

(you can also test vrchat's launch options)

(I use a pico 4)
AMD could improve on VR, I hope it does soon.

[Soupkirby]

Nvidia has near lossless encoding and decoding, while AMDs is well... Not as good, that makes a huge difference for VR performance. Ram speed, bus width, and amount of vram, are some of the most important things when playing VRChat. So I'm not crazy surprised your performance has been not as good, but I do think it should be better than it is.