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View Full Version : Why cant Nvidia do like CF X???


malachi1313
07-31-08, 11:22 PM
You know so you can mix and match cards?? I would love to add my 8800gtx to my 260gtx. Whats stopping this from happening with nvidia products?

DSC
08-01-08, 12:31 AM
You can't mix and match HD48xx to HD38xx, totally different cores. Same with 8800GTX and GTX 260, they're totally different cores.

KasuCode
08-01-08, 01:21 AM
Whats stopping this from happening with nvidia products?

The ice cream truck,



And physics

malachi1313
08-01-08, 03:34 AM
I thought you could mix ATI cores without a performance drop with crossfire x. Am I wrong?

crainger
08-01-08, 03:49 AM
Yep, the cards HAVE to be within the same generation for now. Plans are to have cards from other generations act like a physics co processor.

Bman212121
08-02-08, 12:38 AM
You know so you can mix and match cards?? I would love to add my 8800gtx to my 260gtx. Whats stopping this from happening with nvidia products?

Using the current technique, aka AFR2 (alternate frame rendering) GPU A takes frame 1, GPU B takes frame 2, A takes 3 and so on. This requires both cards to be able to work at the same pace. If one card is faster than the other, it will have to slow down so it doesn't get ahead. In your case it would be like taking the GTX 260 and turning it into another 8800GTX. So the end result wouldn't really be a lot faster.

Obviously, the answer would be something like GPU A takes frames 1,2 and 4 and GPU B takes 3 and 5, but trying to program a dynamic load like that would be really hard to do. There is one method available that could technically scale an off balance load like that, but it didn't seem to be as fast as AFR. The method is split frame rendering, where one gpu take a certain percentage of the screen, and the other gpu takes another percentage. I think the problem was trying to make the image come together correctly and effeciently.

I don't remember how ATI was planning on doing it, but I don't think I've seen it in action before.