OCZ Gold 3x2GB 240-Pin DDR3 SDRAM PC312800

Palit NE5T240SFHD01 GeForce GT240 1GB 128-bit GDDR5

ASUS P7P55D-E LGA 1156 P55 SATA 6Gb/s USB 3.0 ATX Intel Motherboard

Intel Core i7-860 Lynnfield 2.8GHz 8MB L3 Cache LGA 1156 95W Quad-Core Processor

SAMSUNG 22X Optical drive (DVD+-R/RW)

CORSAIR CMPSU-620HX 620W ATX12V V2.2

Windows 7 Ultimate x64

Brand new system (got it from newegg two days ago) and it booted up and installed windows and ran for a day just fine.

Yesterday, I boot it up in the afternoon and run various games at full graphics for most of the day.

I turn on WoW and play for a few hours and it hard stalls. No numlock switching, no mouse feedback but nothing going wrong on the screen. No BSOD.

I wait a bit to see if the stall is just a temporary one, but then force shutdown the computer.

Upon reboot, everything seems fine, windows sees that it didn't shut down properly but I go into normal boot and restart WoW. I'm able to load it up and start running around when it freezes again. This time when I restart, it doesn't even get to BIOS. It starts (power goes on) and it just hangs with no output to the monitors.

I shut it off and went to bed.

This morning, I turned it on and went into BIOS setup. I'm not terribly experienced with messing with BIOS settings but I checked over them the best I could. Everything seems fine so I boot into windows and browse the internet for a bit looking for a solution, hard freeze within 10 minutes. I restart and go into BIOS and check the CPU temperature, 40c.

I'm kinda stumped here. Some people say it might be a memory issue, but why would it take so long for it to come up? Could it have been slowly accessing one memory stick at a time and then it just got to a bad one and that's what is causing it to fail? It seems odd that I don't get a BSOD from a hardware failure. Having the screen just halt with no input or output change seems like a software thing to me.

Any thoughts?