Hi everyone, i have same problem almost 8 months (sinjulia tests freeze pc). It wasn't memory issue. I found solution for me: i just lowered voltage for CPU from 1.20 to 1.15 (also CPU term. from 1.20 to 1.15) and changed RAM voltage from AUTO to Normal. After all - no more freezes and stucks (passed all FPU tests).
Hope it will help somebody.
My specs:
OS: Windows 8.1 Home x64
CPU: QuadCore Intel Core 2 Quad Q8200
Motherboard: Gigabyte GA-G41M-ES2L
Memory: DDR2 4gb 800 (Transcend)
GPU: Gigabyte GeForce GTS 450
HDD: Seagate 500gb Sata II (5400rpm)