Just when I was considering buying a 6950.
Now I'm considering http://www.newegg.com/Product/Productcompare.aspx?Submit=ENE&N=100007709%20600083901%20600007779&IsNodeId=1&bop=And&ShowDeactivatedMark=False&CompareItemList=48%7C14-125-385%5E14-125-385-TS%2C14-150-527%5E14-150-527-TS%2C14-131-378%5E14-131-378-TS
Its quite simple: 1GB take the 6870 - 2GB go for the 6950.
So far everything runs fine with the 6870, and this will be so in the near future. But if you want the best graphics, then 1GB on the card is already reaching its limit.
The 6950 is quite close to the 6870 (~5-10 fps depending on the game), but the one with 2GB still got reserves for AA, HD-Textures, etc.
The good thing is that Crossfire works fine, and if you combine two of these cards you'll notice the difference. Especially if you intend to keep the cards for a few years. For the last few years i've always got either the best midrange/performance card (this time 6870) or the lower high-end card (this time 6950). If i don't have enough power anymore, i'll just add a second videocard and everything will be fine again... The next cards i'll buy will be some Radeon 8XXX - until then i don't expect any problems.
Hey, im going to buy a new computer and im wondering if one AMD radeon 6990 or evga geforce GTX 580 in SLI will be better? Thanks in advance
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If you want to waste your money, then go that route...
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It is far better to get one or two cards from midrange/performance or a lower high-end card. Just make a short calculation.
Year one:
You spend 600 - i spend ~160
Year two:
You spend nothing - i jump a generation, and add a second card (cost now ~300 as the cards get cheaper)
Year three:
You spend nothing, but the card gets outdated - i get a 'new' one with enough power (cost 'til now ~460 - will be less if i sell the old cards)
Year four:
You spend nothing, but the card definitely is outdated - i jump a generation again, and add a second one, have now spent as much as you (aka ~600), but still are up to date...
In the end i'm far more flexible when it comes to new technologies (get a new one instead of adding one), while not having to invest a big sum for one of the best cards. Same goes for the loss of money if you want to resell cards, you'll loose several hundred, i something around 40-50.