Boot / OS problems on new build

Specs:

PII 720
schythe mugen 2 cooler
GIGABYTE GA-MA790X-UD4P
ATI 4890
WD black 640gb x2
corsair 750w psu
specific memory: G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 1066 (PC2 8500) Dual Channel Kit Desktop Memory Model F2-8500CL5D-4GBPK - Retail

History:

All parts brand new. CPU had 2 bent pins which I straightened without breaking. Everything installed fine and it booted into BIOS the first try. Messed around in BIOS for a while, left it on for a day to make sure it was stable on a basic level. CPU temp ~32 C idle.

Problem:

Tried to install Windows 7 RC on brand new HDD.
1) Installation with boot dvd, changed boot settings in BIOS but startup hung on "Boot from CD/DVD:_" (blinking curser). I tried to boot from the DVD on my older computer and I just got hung up on the blinking curser. I thought it might be the optical drive, but maybe its the DVD. However, see 2).
2) Installation from USB flash drive, "Problem loading operating system" error. This led me to believe it was just a problem with Windows 7, so I tried my HDD with XP.

Took a 120gb WD HDD out of my 5 yo computer with XP installed. Starts up but I get a BSoD at the XP splash and it goes into a restart loop. It doesn't stay on the BSoD long enough for me to see what the stop code is. Works fine on my older computer.

After 2 or 3 restarts it wouldn't turn on at all. Had to reset the CMOS with a jumper on the mobo, then it started up fine. I've tried it with default BIOS settings as well as the settings I messed around with.

Tried with 2 sticks of 2gb ram as well as each stick individually.

So I can boot into the BIOS fine, but I can't get past that. I've spent hours trying everything I can think of, I've read the internet and I can't find anything that works. I'm desperate for help.

In your bios, is your memory set to the recommended manufacturer voltage?

You need to do more than just set the timings. You need to make sure the speed is set correctly and set the voltage to 2.1v. I'm guessing the problem is with your burn of the Windows 7 disk. I would burn it at the slowest speed possible. Did you download it directly from Microsoft, or did you use a torrent site? I've heard rumors of trojans and stuff in some of the ones available on the torrent sites. You can download it directly from Microsoft here:

http://www.microsoft.com/Windows/W [...] nload.aspx

Yes, those RAM settings are correct according to the manufacturers specs on your RAM. DDR2 1066 with 5-5-5-15 timings at 2.1v.

What else can I try? I don't want to have to go buy a copy of Vista just to find out that it was something else