OpenGL Programs Load in Safe Mode, but not Normal Mode?

I booted up Poser in Safe Mode and it works. Yet, everytime I try to boot it (or any other OpenGL program) in Normal Mode I get a system freeze.

What are the differences between Safe Mode and Normal Mode? Could it be that Safe Mode uses less exe files?

My System:
E8400 @ 3.0ghz
Sony DVD-RW
Western Digital 500gb HDD
HIS Radeon HD3870x2
Patriot 4gb @ 800mhx 4-4-4-12
Gigabyte DS3L
Rosewill 600w
Raidmax Smilodon
Windows Vista x64

I have Catalyst 8.8 drivers. Anything newer than that results in a system crash.