Abit AB9 Pro, Error 8.7 on boot. Please help!

I have an Abit AB9 Pro motherboard, I love it to death. I have been having on and off problems since ive recieved it. However, this most recent one seems to be a pain in the butt.

I keep getting a error 8.7 when I boot the PC with 3 beeps then shuts off, I have to reset the jumper, remove the battery and keep the pc unplugged for like 30 minutes then plug it back in and it boots. However, if I just to go into the bios making no major changes, just disable onboard sound card, and floppy drive, then save, restart and 8.7 comes back again. I have replaced the CPU FAN, and Power Supply all the other parts have been exchanged (including CPUs e6400 and x6800) back and forth everything else is working fine.

I am running the latest BIOS from Abits website that I applied via the Abit FlashMenu.

According to the error code "Check CPU core voltage Power on -> Stop at 8.7. 12V 4 pin plug disconnected or power supply damage Check 4 pin power plug or replace power supply"

I have done all these things, is my motherboard defective, did I perform a bad flash?

Thanks so much for your time,
Sean

Looks like a PSU fault to me, If possible try another PSU.

Next time you are in the bios check the voltage readings and see if any looks wrong.

I checked the voltage, everything was fine there. Three PSU's still doing it.

However, I think I may of fixed it.

I originally flashed it when I was booting into vista and I flashed with a beta version of FlashMenu. I grabbed the latest version of FlashMenu / Uguru from the abit site and Reflashed with the latest firmware, seems to of fixed the problem, so far so good.

Thanks for the help,
Sean

I too am receiving this error code on my 2nd AB9 Pro (I RMA'd my first because I got a check sum error and had to clear the CMOS every time I booted). 'Puter shuts down before I even see a bios screen. I am reluctant to believe it is caused by my PSU because:

-PSU is brand new Seasonic
-I didn't recieve this error code on my last AB9 Pro that I RMA'd

I checked the MB outside of the case with and without video card and memory without effect. Can anyone give me some ideas on what to do before I RMA this board?