Yeah you'll be fine with the XP-90. I'd personally take a panaflo or sanyo denki (not sure if they make those in 92mm size) or another 35mm thick fan since you'll get better airflow. The denki particularily has good flow/noise ratio. You're all good with what you've listed above though.
Intel C2D E6320 / AMD Athlon X2 3800+
Gigabyte 965P DS3 / DFI nF4 Ultra-D
2GB OCZ Gold PC2-6400 / 2GB OCZ Gold PC4000
eVGA 8800GTS 320MB / eVGA 6800GS 256MB
150GB Raptor / 74GB Raptor
2x500GB / 320GB
OCZ GameXStreme 850w / OCZ StealthXStream 600w