Have to remove CMOS battery to get PC to boot properly

[daktal01]

Unplugged external devices (keyboard, mouse, etc) and moved the PC across the room to sweep the area around it. Moved it back. Plugged in the keyboard and it lit up and then turned off. When I booted up the PC, all fans and lights come on but no power to keyboard and mouse and no video. Tried to turn it off and it would turn back on within 2-3 seconds. Disconected video card, PSU, RAM and drives to reseat everything. Same problem. Removed CMOS battery for a few moments, put it back in and PC booted up fine. Crashed after about 15 minutes, giving same symptoms as before. Repeated CMOS battery removal and it worked. Came here and searched for answers.

 

[Chicano]

Sounds like the BIOS gets corrupted repeteadly... it may also be the corruption isn't removed but replacing the battery may reset it to default settings. I'd suggest resetting the BIOS properly and if doesn't solve it, a BIOS restore would be adviced.

a) Bios reset:
1. Remove the AC power cord
2. Remove the battery
3. Move the BIOS jumper to pins 2 and 3
4. Press the front panel power button and hold it for 30 secs to a minute
5. wait 10 minutes
6. Restore battery, jumper, AC cord and start the computer.

b) A BIOS restore:
Same as a BIOS reset except on point 3. Remove the BIOS jumper completely. This BIOS restore method generally works for any BIOS but if necessary, a second restore should be done according to motherboard manufacturer recomendations so if necessary, I'd suggest searching for a mobo specific BIOS restore method.

 

[daktal01]

Sounds like the BIOS gets corrupted repeteadly... it may also be the corruption isn't removed but replacing the battery may reset it to default settings. I'd suggest resetting the BIOS properly and if doesn't solve it, a BIOS restore would be adviced.

a) Bios reset:
1. Remove the AC power cord
2. Remove the battery
3. Move the BIOS jumper to pins 2 and 3
4. Press the front panel power button and hold it for 30 secs to a minute
5. wait 10 minutes
6. Restore battery, jumper, AC cord and start the computer.

b) A BIOS restore:
Same as a BIOS reset except on point 3. Remove the BIOS jumper completely. This BIOS restore method generally works for any BIOS but if necessary, a second restore should be done according to motherboard manufacturer recomendations so if necessary, I'd suggest searching for a mobo specific BIOS restore method.

Thank you very much. I was afraid it would be one of those issues impossible to diagnose with what little info I had and requiring reports I can't necessarily get. I did not have to go quite this far; removing the CMOS battery the 2nd time seems to have resolved the issue. If it repeats, i will take these steps.