My specs: Q6600+550ti+xp 64 pro+4gb ddr2 memory. Was using win7 , and vista over the years/months. Went back to XP game performance is still like 20%-40% faster over win7 haha. I can only guess because of the less resources XP has, 20-25 at times. PF usage is always like 260mb or 800mb or something. Another interesting thing, when uploading videos to youtube before on win7 i can hardly browse the net, but on XP i can browse the net with little slowdown. less bandwidth? Just some game examples which i tested: NFS HP 2010 1920X1080, MAX = 45-60. On win7 i can't even run this game at 1920x1080 or 1600x900 without the frame rate stuck between 19-30. Hellgate london = 60 all the time lol at 1920 max with full AA 007 Bloodstone = 1920x1080, max, full aax8 = 47-60. Can never play those games like that on win7 or vista. Also another trick i found , may work on win7 , i notice recording to be about 30% smoother using Fraps 2.7.4. Not going to post a link , you have to find it on your own, but recording is much better using a old version of fraps. Bottom line, less resources, faster gameplay it seems. Only flaw with XP, GUI isn't as good, and well can't run dx11 or dx10 games, not really a big deal atm. I am building my AMD build soon( secondary computer ), going with a 8 core , 12gb of ram, 7850 2gb computer with win7. I will post up some videos later, going to be testing for a while and trying out games.