Hmm. What are the BIOS settings? DO you have the latest BIOS? Did you recieve that last panic in snow leopard or during boot?

In snow, you do not need Busratio=20 or CPUS=1 with a DSDT Patch

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OS: Snow Leopard Mac OS X 10.6.2 (10C540) | Vanilla Kernel | 64 bit Kernel | EFI64

CPU: Intel Core i7 920 @ 3.6 GHz
GPU: 2x SLI Dual GTX 260 (OpenCL working)(QE+CI)
RAM: 6GB DDR3 1600MHz 7-7-7-20

AUDIO: Realtek (5.1 config)
HDD: RAID 0- 1 + 1TB HDD's | 320GB HDD
MOBO: MSI X58 Platinum SLI (Intel ICH10)

CASE: Haf 932 Full Tower Case + Red Cathodes
MONITOR: Asus VK266H 26" 1920x1200 LCD

All working