CMOS checksum error – Defaults loaded!?!

  Fatboy415 19:31 24 Sep 2008

I’m posting this in complete desperation. In over 10 years of assembling and modifying my own PC’s I have never once had this problem.

I’m in the process of building a basic PC for my nearly ten year old son.

I started with a fully working system comprising of a Gigabyte 8LD533 motherboard and Pentium 4 Northwood 2.4 GHz socket 478 processor in a generic beige box.

From work I was given a snazzy HP desktop case with all the workings, except the motherboard had failed.

All I have done is transplant the innards from the beige tower into the black HP and this happens.

Boot up PC…one beep (Great!)…then the internal speaker connected to the motherboard goes berserk as soon as it reports the memory frequency of 266 MHz.

It then reports the drives inside the machine then comes up with what I am beginning to think are the terminal words “CMOS checksum error – Defaults loaded”

Whilst all this is happening pressing F1 or DEL does nothing so cannot enter the BIOS to correct the settings.

In the end the PC just turns itself off.

So far I have:-
• Replaced the power supply.
• Tried 4 different CMOS batteries.
• Tried 4 different sticks of memory.

With no effect.

The only thing I can report is that the lights do not come on on the keyboard. I will try tomorrow another PS2 keyboard.

All help much appreciated as always.

Thank you,
Michael Clare

  Terry Brown 20:53 24 Sep 2008

I'm guessing you have damaged the BIOS .
Do you have a BIOS 'short jumper'?
Normally located near the battery,it will be 3 pins with either 1 & 2 or 2& 3 connected.
Whichever it is reverse the jumper (i.e. if you have 1 & 2 connected, change it to 2 & 3).
This will discharge the bios, and reset it (provided you have not damaged it)to factory defaults.

You could try starting it in the reverse position, some boards will start others will not.

Leave it in the reverse position for about 2 minutes before switching back to normal.

Have a lok at this page for suggestions. click here

  gary2112 21:45 24 Sep 2008

or if you dont have a jumper take the battery out with flat end screw driver leave the battery out for a least one minit then replace .all so ,this could be another warning as some bios beeps do that when the cpu fan is not connected in the write way as this is a lock down to stop you from damaging your cpu first take the battery from the mother bord.if this dont work.remove the heatsink from the chip take out the chip and in a smooth even finish use artic past on the chip replace fan .if you still have problems .the grafix card does it have its own power supply ie connects to the psu .if so take the power connector out and then replace

  woodchip 21:54 24 Sep 2008

If this is a new Motherboard Make sure Clear CMOS jumper is in Run position it will be found near to CMOS battery

  €dstowe 22:12 24 Sep 2008

Ensure that the mounting posts for the motherboard to chassis are all present and correct and there are no short circuits from the board to the case.

  Fatboy415 06:44 25 Sep 2008

Thanks for all of those.

I did run the mb on top of a lump of Polyethylene foam and still had the same problems so have discounted a short circuit.

Left the battery out for 30 mins and still the same.

I'm interested in the 3 pin's option. Like you say Terry they are next to the battery but didn't have any pins covered. I will try this tonight otherwise it's a Novatech barebones system.

Thanks everyone

  €dstowe 07:53 25 Sep 2008

"Like you say Terry they are next to the battery but didn't have any pins covered."

I'm pretty sure you need a jumper over one set of pins to enable the battery to work properly. There is a reset position and a run or normal position.

  [email protected] 10:11 25 Sep 2008

This board needs a jumper on J1 (located near the battery). Pins 1 to 2 are the normal running position and Pins 2 to 3 reset the CMOS.
Put the jumper on 1 to 2 and leave for a minute or two to reset CMOS, then transfer the jumper to 1 and 2 and m/c should start in default mode but hopefully without a check-sum error.
IF this fails then I'm afraid the CMOS is cream-crackered.

  woodchip 11:24 25 Sep 2008

There should be a jumper on the three pin covering just two pins, I think the Run Position is pin 1 and 2. And 2 and 3 clears cmos. You may have to try it to find out which way

  Fatboy415 12:26 25 Sep 2008

Thanks one and all. I think the reset pins are my my last chance. If this doesn't work I think it's a new motherboard or sell for parts.

Consider this as closed.


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