Which graphics card is better for gaming?

The nvidia gtx580 sli

Or

The amd radeon hd6990 crossfire?|||hi adam, dig this man this is a fact okay you picked out two choices now let's look at your chioces for gaming the Nvidia geforce 580gtx is a good card if you are not a gamer so you need a card that is for gamers and the amd radeon hd 6990 too much power and this will make your computer freeze because it is too hot when gaming too long so what i recommend a Nvidia geforce 9800gtx. the reason why is that the nvidia geforce 9800gtx is a gaming video card the reason is that cuts back on vibration and especially the heat. but may i be honest with you? what you really want is killer graphics and to protect your computer for the heat factor so what i recommend iif you have an extra sli slot than a radeon 4870 and below with the Nvidia geforce 9800gtx but if you do not have that sli slot than what you should lean toward is just the Nvidia geforce 9800gtx. these are the best for any computer good luck hope i was helpful to you|||nVIDIA gtx580sli|||I will go with nVIDIA gtx580sli|||If you are talking about GTX580 SLI and 6990 CF, (and not 6970 CF) I would take 6990 CF as it's a Quad CF (6970 * 4). But make sure you have a beefy PSU to handle the load and an OCed SB. I also hope that you are going to play at 2560*1600.