AMD vs Nvidia - VR edition

andybird123 said:
Typically VR games have tended to run better on Nvidia hardware, so just because game X runs well on an AMD card doesn't mean that's going to be reflected in all VR games
Click to expand...

Yeah just wondering how VR performance is any different from normal performance, isnt it essentially doing the same thing? Is it drivers?

These new cards look pretty powerful, I would expect(hope) both Nvidia and AMD have strong performance.
 
chroniclard said:
Yeah just wondering how VR performance is any different from normal performance, isnt it essentially doing the same thing? Is it drivers?

These new cards look pretty powerful, I would expect(hope) both Nvidia and AMD have strong performance.
Click to expand...

Well with "normal" performance you still get games that run better or worse on either set of hardware, a lot of VR games have much smaller teams/budgets and so spend less time on optimising for specific hardware.
 
Glowballs said:
Seen loads of 3090 for around £1500/1600 lately since AMD gpu announcement. Just keep your eye on parts alert pages or the discussion group on hotukdeals and you'll get one soon.
Click to expand...
Seen the odd 3090 crop up on competitor websites past week or so. I think there will be more stock of these than 3080 pretty soon.
I have managed to resist so far but the itch is getting worse. At least I would not have to sit around waiting for the 3080ti or whatever it is gonna be to be released.
 
With the AMD cards having a USB C port directly on the card backplate, and Nvidia cards not having this, what impact might this have on visual performance on the Quest 2?

One might hypothesise that a direct connection to the GPU might be faster than having to route through the motherboard and a front USB port? Not sure if that's how it works though.
 
danlightbulb said:
With the AMD cards having a USB C port directly on the card backplate, and Nvidia cards not having this, what impact might this have on visual performance on the Quest 2?

One might hypothesise that a direct connection to the GPU might be faster than having to route through the motherboard and a front USB port? Not sure if that's how it works though.
Click to expand...

It might be more reliable, given that some motherboards have dodgy USB3 support.
I have a USB C socket on the front of my PC, which is rock-solid when using Quest link.

Another use for the graphics card USBC socket is to power devices like the Valve Index which currently need an external power adaptor in addition to a USB connection.
 
danlightbulb said:
With the AMD cards having a USB C port directly on the card backplate, and Nvidia cards not having this, what impact might this have on visual performance on the Quest 2?

One might hypothesise that a direct connection to the GPU might be faster than having to route through the motherboard and a front USB port? Not sure if that's how it works though.
Click to expand...

No, it works entirely over USB which is always controlled by the CPU, if anything adding in extra hubs would add latency, not remove it (though in practice this is negligible)
 
andybird123 said:
No, it works entirely over USB which is always controlled by the CPU, if anything adding in extra hubs would add latency, not remove it (though in practice this is negligible)
Click to expand...

Hmm interesting. So the GPU itself cannot directly output a compressed video stream via its internal USB port, it has to back and forth communicate with the CPU to do so?
 
danlightbulb said:
Hmm interesting. So the GPU itself cannot directly output a compressed video stream via its internal USB port, it has to back and forth communicate with the CPU to do so?
Click to expand...

This is one of the things I'm hoping improves performance when I get the G2, coming from the Quest 1 + Link cable. Instead of streaming compressed video with the overheads that brings, the image is going directly from graphics card to the HMD. Not sure exactly what sort of difference I'd expect to see, certainly I think there should be a very noticeable visual improvement, aside from the obvious huge jump in resolution.

As it seems unlikely that I'll have a new Graphics card by then, I should be able to test on a similar resolution to the quest by downsampling, and get some idea of how performance might be affected by the link's compression.
 
danswan said:
This is one of the things I'm hoping improves performance when I get the G2, coming from the Quest 1 + Link cable. Instead of streaming compressed video with the overheads that brings, the image is going directly from graphics card to the HMD. Not sure exactly what sort of difference I'd expect to see, certainly I think there should be a very noticeable visual improvement, aside from the obvious huge jump in resolution.

As it seems unlikely that I'll have a new Graphics card by then, I should be able to test on a similar resolution to the quest by downsampling, and get some idea of how performance might be affected by the link's compression.
Click to expand...

My GPU isn't good enough for me to properly test Quest 2 compression, but reports seem to say that when the bitrate is raised the compression is not noticeable. We're still hindered by the link resolution though I believe, which we're waiting on Oculus to do an update for.

Its interesting where that compression is being done though -is it on the GPU or CPU? If CPU, then games over Quest 2 could benefit from a better one.
 
According to this, "the PC compositor encodes the eye textures -- surfaces that an application submits to the compositor -- using H.264 video compression, and sends the images as slices to the remote client over USB."

I think that compression would probably be done on the GPU wouldn't it?

*edit* same question asked (and answered) here
 
Video compression is done on the GPU, which is why Link works better on Nvidia cards which have better video compression. It does add some overhead onto the GPU over and above what is required to render the game graphics.
 
Just got my 3090 today and this thing seems to be rinsing through my VR titles on the index. Only had a quick go on a few titles but Asgarths wrath all epic settings 150%SS and the CPU is now my bottleneck (7700k soon to be replaced). Starwars squadrons all ultra settings 150%SS pretty much 90fps solid no problem. Fallout4 was breezing through 120fps.

Coming up from a 1080ti I would say either the 3080/ 6800 xt would just be amazing for VR
 
kevman said:
Just got my 3090 today and this thing seems to be rinsing through my VR titles on the index. Only had a quick go on a few titles but Asgarths wrath all epic settings 150%SS and the CPU is now my bottleneck (7700k soon to be replaced). Starwars squadrons all ultra settings 150%SS pretty much 90fps solid no problem. Fallout4 was breezing through 120fps.

Coming up from a 1080ti I would say either the 3080/ 6800 xt would just be amazing for VR
Click to expand...

I really want a 3080, but I think I'll have to wait until after Christmas now.
 
danlightbulb said:
Hmm interesting. So the GPU itself cannot directly output a compressed video stream via its internal USB port, it has to back and forth communicate with the CPU to do so?
Click to expand...

This was not quite the intention of virtuallink, which is the USB-C port on your GPU, is a regular USB port, in addition carrying more power and a displayport connection, with the intention of it having a single cable connection rather than the triple headed connectors of the index, vive, etc.

It hasn't really met with widespread adoption, but if you plugged a Quest 2 into it, it would only be using the USB portion in the same way as any other USB port and would have no lower latency or processing overhead. The GPU framebuffer still needs to go off to be compressed, sent to the usb controller, etc, which still involves the CPU, rather than going straight from the GPU to the displayport link in the virtuallink port.
 
Installed the 3090 and tried a few games. Project cars 2 is just sublime, not a single frame drop, no repro, no stutter. ACC i had running stable on the old 2080ti with a little repro and dropped frames, now i get no drops or repro it glides. Not touched the visuals because i'm happy with the default epic [email protected]. Tried Contractors with every setting to ultra as it would struggle with the frame rate on the 20ti, it holds 90 now. Lastly some of the 4k visual pinball tables would struggle before on multiballs, now they just don't.

Very happy, project cars 2 was just another level of stunning, i eagerly await to the G2 to see if it does it for a 3rd time.
 
lokiss said:
Still want the 3090. The only dilemma at the minute is dropping 2 grand on a scalped card, it's becoming that tempting.

As appealing as the AMD prices are, i think Nvidia soft and tech are more involved in the VR space and more likely to get picked up by developers.
Click to expand...

Your what the problem is in the market
 
You must log in or register to reply here.
Back
Top Bottom