Checksum Error and ASUS Mobo

[Anthony903]

Hi, I'm hoping you guys can help me out cause I've tried EVERYTHING and I can't fix this problem with my P5N-D motherboard.

Basically when I restart or shut down my computer I can't post on the next startup. The computer will show the bios screen then just turn off. I have to open the case, clear the CMOS through jumper and once I turn the computer on, it will be stable until I turn it off or attempt a restart.
Also everytime I make it to post, I see CHECKSUM ERROR - Loading Defaults

Here's a list of all the things I've tried to remedy the problem with ZERO success:

- Swap out PSU, Video Card, RAM, with working parts
- Put just one stick of RAM in all four slots
- Unplug all HDDs and CD drives and boot without them
- Take out CMOS battery and put back in
- Try a different working CMOS battery
- Put mobo in another working case to determine if case switches are the problem
- Bareboned switch to just POWER SW and still problem persists
- Test different voltages on the mobo/CPU/RAM but NOTHING saves on the BIOS.
- Updated BIOS to latest version via Flash Drive
- Checked to see if BIOS chip was seated correctly and it is

Once I get into Windows I'm ok and the motherboard is stable and doesn't shut down. It's just I can't make any changes to the BIOS or restart/shut down the computer or else it will just keep crashing (shut off) while attempting to post.

I've spent hours on the internet researching possible solutions to this problem, but they all were dead end threads or something I've already tried. Please help!!

My specs:

Intel Core 2 Extreme QX9650
2x1 GB Corsair XMS2 DDR2 800
2x WD HDD @ 150 GB each
Nvidia Geforce 9600 GSO PCI-E
ASUS DVD-RW drive
Zalman Z-Machine GT1000 Case

 

[Anthony903]

Well I figured it out for anyone who is searching on the internet for this very same issue. My CPU went bad. Popped in another Core2 and everything was stable.