Question by Muki: When troubleshooting a computer, when might you have to enter CMOS setup?
I have a few books about managing and maintaining a PC which I looked through many times and searched online multiple times and cannot seem to find an answer. I am looking for about 3 or 4 reasons to enter CMOS when troubleshooting. Please help.
Best answer:
Answer by jdinvis
I would enter the BIOS (not CMOS, incidentally, that’s the battery!) if a device was ‘mysteriously’ not showing/working in Windows.
I would enter the BIOS to check that said device wasn’t disabled.
For example, say you install an upgraded Video card instead of using your on-board graphics processor (GPU), you may need to disable your on-board GPU for the machine to ‘realise’ that it should output to the other card.
Then, the card goes bad and you have to remove it. No output to the other socket?? Check your BIOS, re-enabled the on-board GPU to get that going again.
For one…..anyone else?
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Exactly what the person above stated…so i thought 2 ppl agreeing would help you. CMOS is nothing more than that little lithium battery that holds the memory of the hardware. And also the internal clock. This is why you can turn a computer off and a week later turn it on and the time is correct. Now, what you can do is if someone has a password connected to their BIOS and forgets it…you can remove the CMOS battery for a while and sometimes there is a jumper right next to it that will clear the BIOS password then that person can get to the windows boot screen.
Hope this helps a bit
if your repairing windows using a floppy or cd program you need it to ,change boot order, if you add a hard drive or disc player that dosent work, you can find out if bios even recognized it, if your buss or processor isn,t running at proper speed, you can check and change settings, you can enable a bios password, you can change the start up screen to show diagnostics or not