Windows Vista/7 Hangs on Start-Up

I recently purchased a new motherboard and salvaged some parts from a spare pc. The components are as follows:

Gigabyte ga-ep43-ud3l motherboard
Intel Core 2 Quad Q6600 2.4 GHz
GSkill 2x2GB sticks DDR2 800 RAM
ATI Radeon x1950 PCI-E
75 GB SATA 10000 RPM drive

As you can see, not the newest kid on the block but still pretty decent. I've tried installed the 32-bit and 64-bit business versions of both Windows Vista and Windows 7 and all attempts end in the system locking up on the Windows splash screen at startup. However, Windows XP 32-bit installs without any problems. A friend of mine had a similar experience with his Asrock board but doesn't completely remember what he did to fix it but it involved removing sticks of RAM and playing with RAM voltages in his BIOS until things worked.

Does anyone have any concrete answers to this problem?

Thanks in advance