Windows 7 - CPU Spiking - random shutdowns

Hello all,
Just finished building phase 1 of my "dream" rig. I am not so much focused on gaming, but I wanted a good RAID system with some multimedia functionality and strong data processing capabilities. The problem I'm having is that all 4 cores of the CPU will spike to 100% about every 30 seconds, and every few hours the system will shutdown, and on reboot I get a BSOD, recovery manager comes up and the machine is able to recover. I have attempted to determine what is causing this by monitoring the performance tab in task manager as well as the resource monitor - however, I am unsure of what exactly I am looking for. The CPU spiking seems to be related to the Hauppauge capture card that I am running, because the spiking is not present until I attempt to watch live tv through MCE, and will not stop until a reboot. Any suggestions to follow would be greatly appreciated. Also overall the machine is sluggish, for having a strong chipset and 8gb of ram.

The rig currently is: Intel DP67BGB3 Mobo, i5-2500 CPU, 8gb Ram, (2) WD1600AAJS 160 gb drives in a RAID 1 configuration (strictly OS and Programs) controlled from the intel board, ATI radeon HD 4350 graphics card (going to be replaced this week with a MSI GTS450 card), Hauppauge WINTV PVR PCI II (26xxx) capture card (replacing with a Hauppauge HVR2250 because of known problems with the WINTV on 64 bit systems, this week), monitors are a Viewsonic VX2433wm (VGA) and a Mitsubishi 46" TV (HDMI), running analog sound through a sound blaster 2.1 speaker system, and finally a LaCie 2tb Big Disk Quattra running eSata until I get the 3 drive RAID5 installed.

Phase 2 will be the addition of a RAID5 storage system running from the intel board using (3) WD 3tb drives and removing the Big Disk Quattra from the system.

Lots of details I know, but again I'm not sure what the issue/conflict may be. Thanks for the help!