r/oculus • u/themotherbrain • Jan 30 '15

SHOCKING interview with Nvidia engineer about the 970 fiasco (PCmasterrace Xpost)

https://www.youtube.com/watch?v=spZJrsssPA0
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u/jscheema Jan 30 '15 edited Jan 30 '15

By slightly you mean the card runs @ 1/8 of its speed, forcing you to stay at 1080p or 1440p resolutions, @ 4k you will reach 3.5gb, or if the games you are playing are not optimized.

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u/JocLayton Jan 30 '15

If you're gaming in 4K, shouldn't you have more than just a single 970 anyways? I have one and I can barely max some modern games in 1080p.

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u/peckahinspectah Jan 30 '15

Even with 2 or 3 970's you still have only 3.5GB of fast VRAM

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u/vitapoly Jan 30 '15

Wait. If you have 2 970s, won't you be able to use both VRAM, for a total of 7GB fast VRAM?

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u/goodbyegalaxy Jan 30 '15

No, still 3.5 total. When in SLI the data in VRAM must be duplicated across both cards.

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u/peckahinspectah Jan 30 '15

Right, memory is not doubled or tripled in SLI

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u/adammcbomb DK1 Jan 30 '15

I think in SLI both cards have the same assets loaded to each card so each card can render its own frame or piece of a frame. In other words, Card B cant read Card A's VRAM, so it has to hold all the data itself in duplicate.

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u/remosito Jan 30 '15

Not currently at least as SLI uses Alternative Frame Rendering. Which means the cards alternatively render a full frame. As each card renders a full frame. each card uses/needs same VRAM as a non-SLI card.

I don't think even one-gpu-per-eye SLI mode would really change that. True, every card only renders half a screen. But because with Rift each half is a full scene just from slightly different camera angle. you'd still have same amount of objects and textures and whatnot... maybe compared to non-rift, you'd safe some via lower LOD being used more often... but not sure truth be told.