I was hoping someone would be able to shed some light on what is going on with my PC... It's a brand new build of Vista Business x64 with SP1, along with an AMD Phenom 9550, 4GB RAM, Asrock ALiveDual-eSATA2 mobo, and an (old-ish) Inno3D Geforce 7600 GS (AGP). Now, as you'd expect this flies along quite happily on the desktop, but the problem comes when gaming. I can easily reproduce this problem with FSX, so I'll use it as an example. Load the game, and for the first ~2 mins all is fine, decent framerates, menu animation is fine, you know the score. Then it slows to a crawl - 1 frame every 3 seconds kinda crawl. Exit out of the game, and the whole machine is now slow - browsing net and the scrolling is juddery, same with folders and documents. 1 core seems to be heavily loaded, but after a while it subsides, but the problem remains. Now, change back to the Vista Basic theme, and it all flies again (apart from the gaming, which is still knackered). So, a reboot is done, and the whole cycle repeats. I was thinking something is overheating, but the graphics card has been heavily used in the past and showed no issues, while the CPU fan hasn't spun up (as it does when loaded). All fans are fine. Tried different driver sets (the ones pre 174.85 seem to give 2D corruption) with the same effects. So I'm stumped. Any ideas on what else to try would be appreciated!