Computer locks-up ten minutes after boot, then fine.

Have a strange issue on my new build. After about 5-10 minutes after a cold start the computer locks up and power must be recycled to recover. After that point, the computer runs fine. I got one error report after one of the lock-ups, it and said it was video driver related (STOP 0x000000EA THREAD_STUCK_IN_DEVICE_DRIVER (Q293078)).

I have all the updated drivers plus it did it when I ran memtest, but after the reboot, memtest ran for 12 hours straight. In other words, I have no issues except for this lock-up and it only happens within 5-10 minutes of a cold boot.

I've checked my cpu and video card temps they look fine, in fact I can overclock the video card 10-15% with no issues (besides it running a bit hot). The mem timings were changed, but no effect.

Here is my build.

GIGABYTE GA-N650SLI-DS4 LGA 775 NVIDIA nForce 650i SLI ATX Intel Motherboard
Kingston HyperX 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model KHX6400D2LLK2/2GN
EVGA 640-P2-N825-AR GeForce 8800GTS 640MB 320-bit GDDR3 PCI Express x16 HDCP
Intel Core 2 Duo E6850 Conroe 3.0GHz LGA 775 Processor Model BX80557E6850
OCZ GameXStream OCZ700GXSSLI ATX12V 700W Power Supply

Antec Nine Hundred Black Steel ATX Mid Tower Computer Case
Western Digital Raptor WD1500ADFD 150GB 10,000 RPM Serial ATA150 Hard Drive
SAMSUNG SpinPoint T Series HD501LJ 500GB 7200 RPM SATA 3.0Gb/s Hard Drive
LG 18X DVD±R DVD Burner Black E-IDE/ATAPI Model GSA-H54NK
Hanns·G HG-281DPB Black 28" 3ms Widescreen HDMI LCD Monitor

I still have time to send back the video card since I suspect that this is the issue, any ideas?

I consider myself a pretty good troubleshooter, but this one has me baffled.