No POSTing after adjustments - dead CPU?

System Specs:

CPU: i5-750
MB: ASUS P7P55D Pro
Video: GTS 250 1gb
RAM: 2x 2gb OCZ3G1600LV4GK
PSU: OCZ 600W Stealth
HD: Samsung 1.5TB

I've been having some issues with my memory not being correctly recognized in W7 64-bit (OS reads 3gb when 4gb present) so I updated the BIOS in an attempt to fix it. I had my CPU OC'd to 3.2ghz and the BIOS update reset that to default so I fixed it. Upon reboot, the system wouldn't POST and the CPU red light on the mobo came on. System stayed on, all fans running. I cleared CMOS and it booted to Windows.

I then shut down and reseated my ram into slots 2/4 instead of 1/3 to try to get the RAM issue fixed. System again doesn't POST, but this time there are no warning lights. I put the RAM back and still can't get the system to POST. I took my CPU out and saw some slight markings on the bottom (pics spoilered due to size). Is it possible that my CPU is burned out? I should also mention that this system had been running stably since Nov 09. Any help would be appreciated.