Help with Hardware Interrupts

I just did a clean install of Vista Ultimate x64, when my computer started to freeze up. I opened up Sysinternals Process Explorer and sure enough Hardware Interrupts were hogging all the CPU.


I reinstalled Vista again and still the same problems


Hardware
Intel E8400 (Not overclocked)
2 PNY 8500gt's
EVGA 780i
4GB OCZ Ram with Heatsink
LG DVDRAM Optical Drive
Lite-On DVD-RW Optical Drive
2 Seagate 250GB 7200RPM HDD's in Raid 0



Programs installed
-MS Office 07
-Nero 7
- PowerIso
-WinRar
-uTorrent
-Google Chrome
-Thunderbird
-BitDefender 09 Total Security
-Vent
-TuneUP Utilities
-Skype


Drivers are installed and up to date for everything I have, straight from the manufacturers website.


Ran MemTest 86 and everything came out fine.


I have the computer running right now and it is taking up 50% of the CPU (100% of Core 0), so I have set the affinity to programs im currently using to Core 1, so I am effectively running at half the speed.
I could use a little help here.