I'm attempting to get Snow Leopard running on my system, but after installing, the hard disk won't boot. It just restarts right away. I'm new to this, but from what I've seen specs mean everything, so here's what I have:

Gigabyte EP45-UD3L Motherboard Chipset Model P45/P43/G45/G43

Intel Pentium D 915

Geforce GTS 250 GPU G92

Western Digital Caviar Blue 640 GB HD


Realtek RLT8168C(P)/8111C(P)

Like I said, I'm new and I don't really know what I would have to install in the 'Customize' section. Please and thank you for your help.