So lately I've been playing some MMOs and been having some very serious issues with them. I will get these crashes at random points of playing that bring my computer to a halt for a few seconds, and then the computer reboots. This occurs pretty much randomly with no reason for it doing so. Currently running an iMac with: Windows XP Pro ATI Radeon X1600 - 256mb graphics card (I think this may be my problem) intel p4 dual core 2.5 ghz processor 2gb ram I surpass the recommended for Everquest 2, and meet the recommended for Warhammer Online. The problem with my crashes is that they don't come coupled with an error message, the game just freezes, stutters, and I have to reboot my computer. These crashes are also very random. I can play for hours on end before it happens, it could not happen at all, or I could crash within minutes of logging in. Yesterday I only crashed once, and today I didn't crash for several hours, crashed, logged back in and crashed within 5 minutes. I could be sitting in town and I crash, or doing intense PvP and I crash. Likewise I could do PvP with many players and spell effects on screen for hours and not crash, go away for a few minutes afterward in town to make a sandwich, come back, and be back in OS:X! There's no consistency to these crashes so identifying a cause is pretty much impossible. Things I've tried -disabling autoreboot on system failure (apparently not a system failure) -underclocking my graphics card (using ATItool) -increasing fan speeds (it's not overheating) -lowering settings in the game (nothing still) -updating my drivers (nope) The list goes on, but I've tried pretty much everything I can think of, and still get these horrid crashes. One thing to note is that I only crash when playing MMOs, specifically Warhammer and Everquest 2. On the same exact computer I've played Oblivion and Spore, non MMOs that have much higher requirements than the WAR and EQ2, but I never encountered any problems. I've played: Gothic 2 Black And White 2 Oblivion Team Fortress 2 Guild Wars Spore and none of these ever gave me the problem I'm having now. A few people I've seen post say they upgraded to Vista from XP and their crashes stopped, but after they posted about it once I didn't hear from them again so I don't have enough evidence to say this is the case for sure. I'd buy Vista to be able to play again but I need to know for sure it's the problem. The one problem I pointed out in the beginning was my graphics card. I heard that EQ2 and WAR are optimized for nVidia cards, but I don't think it should really matter as long as it as the proper amount of memory in it. Even so, there is no way to change a graphics card with an iMac is there?