BSODing for months, getting worse, tried everything


My computer has been BSODing since early summer. I've tried literally everything I can think of. All my drivers are up to date, I've taken my computer apart, checked every connection, cleaned everything with compressed air, cooling is sufficient, ran memtest and chkdsk, etc. etc.

It used to only happen when I was running recent-ish games (Fallout 3 mostly) for a few hours, but now I can't run any resource-heavy application for more than ten minutes and sometimes it BSODs when the most I'm doing is listening to music on Windows Media Player. I only bought this computer less than a year ago and it ran perfectly for about 6 or 7 months until this problem started, gradually becoming worse and worse.

Windows 7 x64

Asus M4A79XTD EVO motherboard
AMD PhenomII X4 965 3.4GHz cpu
4GB Kingston DDR3 ram
ATI Radeon HD5770 1GB GDDR5 PCI-e graphics
M-Audio Firewire Solo interface for sound (I'm running studio monitors (speakers). They have their own seperate power sources.)

The BSOD errors are all completely different. I seem to get the same 6 or 7, including IRQL_NOT_LESS_OR_EQUAL, BAD_POOL_HEADER, MEMORY_MANAGEMENT, BUGCODE_USB_DRIVER.

Attached are the latest 3 bugdumps. Thanks!