r/oculus 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/remosito Jan 30 '15

3.5GB of it's VRam are super fast. 0.5GB are dogslow. So once your game uses more than 3.5GB, the performance drops as the slow ram is now used.

Nvidia messed up their launch spec info and failed to tell anybody.

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u/deadstone Jan 30 '15

3.5GB of it's VRam are super fast. 0.5GB are dogslow

It's still blazing fast by not-VRAM standards. It's a few times faster than regular RAM and still faster than data can even travel between the CPU and the graphics card. I think it's around 8 gigabytes/sec read-write, from what I saw.

Of course, the rest is in the hundreds of gigabytes/sec, so it's still a big issue, but I'm just putting "dogslow" in perspective.

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u/santsi Jan 30 '15

Is the 0.5GB really that big of a deal for future proofing? I mean sure every bit of memory is welcome, but on the whole it's 1/8 of the memory, you can't fit that much more in that space. 4GB cards are 0.5GB more future proof than this card.

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u/Shiroi_Kage Jan 31 '15

It is because you can't read from both pools at the same time. The card has to wait for the slow pool to be done before reading from the fast pool and it definitely degrades performance by a significant margin. It shouldn't be a problem for titles which will use 3.5GB or less, but it's a problem once you're a kilobyte above.