CMOS checksum error

  slowhand_1000 23:28 06 Oct 2005

New build pc

Antec Sonata case and PSU

ASUS A8N-E m/b

AMD64 3000

2 x 512mb Crucial RAM

80GB Maxtor Sata 150

128mb Sapphire X700 PCIE card

Terratec soundcard


After getting help from the forum in sorting out the boot up problem I had click here all seemed well. Or so I thought.

After sorting the boot up problem I switched the pc off at the mains. Didn't get to touch the thing again until today and got a CMOS checksum error on start up. So I went into the BIOS and reset the time, date and one or two other settings and restarted. All seemed well all day until I needed to switch off the power. On restarting I got the CMOS error message again.

I took out the battery and moved the jumper to pins 2+3 to clear the CMOS. Restarted, reset the BIOS and all was well again. That is until I swiched the power off again. I must have reset the CMOS now a dozen times but each time the power goes off (even for just a few seconds) the CMOS message appears.

I've taken all non essential cards/drives off the pc and even put a new battery in. But to no avail it seems. I'm now thinking that the motherboard is at fault, unless anyone can think of anything else.

Apologies if I've missed any essential information out.



  woodchip 23:32 06 Oct 2005

Are you sure the Clear CMOS is in the run position

  DieSse 23:48 06 Oct 2005

If the CMOS has a checksum error, and both a clear and a new battery don't fix it, then there is indeed a motherboard problem.

If you can find the CMOS chip AND it's plug-in chip, then try pressing it firmly into it's socket.

Otherwise, contact your supplier about a replacement motherboard.

  slowhand_1000 01:30 07 Oct 2005

woodchip - Yep, checked that the number 1+2 pins are covered (left and centre pins)

DieSse - I can only see one chip that looks like a plug-in and that seemd to be seated ok.

As a last resort I've just sat the board on cardbord so it's not touching anything else. And it's still returning the CMOS error.

So it looks like I'm off to Micro Direct in the morning. I'll post the outcome (good or bad) when replacement board is fitted.

  slowhand_1000 13:48 10 Oct 2005

Sorry about the delay in ticking this resolved.

I took the board back to the supplier and he confirmed that the CMOS chip was faulty. Got a replacement and all is well.

They did ask me though if I had flashed the BIOS. I told them that I hadn't and they replied that I should have tried that 1st. I explained my concern in that if I had flashed the BIOS and really messed it up would they have replaced it. No reply was the answer.

This thread is now locked and can not be replied to.

Elsewhere on IDG sites

Fujitsu Lifebook P727 laptop review

Microsoft Paint set to die after 32 years

Mac power user tips and hidden tricks

Comment désactiver la saisie intuitive et paramétrer votre clavier ?