Currently I have a Radeon HD 4890 1 GB. I'm looking to upgrade soon, and was looking at this:
Newegg.com - PowerColor AX6970 2GBD5-M2DH Radeon HD 6970 2GB 256-bit GDDR5 PCI Express 2.1 x16 HDCP Ready CrossFireX Support Video Card with Eyefinity
How much of a performance gain could I expect from switching my 4890 for that?
Well first off, in the way of compatibility the 6970 is a dx11 card where as the 4890 is a dx10 card. This opens up tesselation and a whole slew of cool dx11 effects improving games that support it.
the new card also has a much larger number of streams in it. This will lead to much better shading support, and even on the fly video conversion (if you use that feature)
For me it wouldn't even be a matter of performance (even though the 6970 would HAVE to perform better)
I can tell you my 5850 totally blew my sli 8800gtx's away. The single 5850 totally destroyed the performance of two dx10 cards.
Can't find any reviews that have both of those in it but considering that the 5870 is faster than the 4890 and the 6970 is faster than the 5870, use these two to get an idea as to how much faster,
AMD Radeon HD 5870 1 GB GDDR5 Review - Page 1/34 | techPowerUp
HIS Radeon HD 6970 2 GB Review - Page 1/33 | techPowerUp
the 6970 will be over your 4890.
Having just moved from a 4890 to a 6950 2gig card I can say you will see a performance difference. I'll also add that games look a little better with the 6950. Also effects like fog, smoke, fire, water and stuff looks better with the 6950.
Played Dead Space on both the 4890 and the 6950 and the 6950 had better looking effects. Same with FEAR 2, the 6950 really came through here.
Overall a really good card (the 6950) so I'd imagine the 6970 would be the same except it's faster than the 6950.
You can also unlock the 6950 to a 6970 with a upgrade - Sapphire Radeon HD 6950 2GB Unlocked to HD 6970 :: TweakTown USA Edition
I haven't done mines yet, but I may soon.
Here's my card - Which ATI 6950?
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