Is a 2600 xt agp better than a 6800gt agp? The reason I ask is that have a 939 socket motherboard and was thinking about replacing the 6800GT with a HD 2600XT. I use the computer for some of my older games, I am not looking to change anything else just possibly the video card. I also use WinXp Sp3 for my operating system on this computer. The 6800GT runs fine just thought about trying something different. 