CPU not starting up

[krv5vignesh]

One day my CPU just did not start up.When i switch it on,the fans rotated for about3 second and then stopped nothing else happened.Then i unplugged the hard disk,dvd drive and plugged it again and started my CPU.It worked as normal.

But when i restarted it it again showed the same signs(fans running for a moment and turning off) and didn't start up.So i repeated unplugging and plugging the all cable going to the motherboard until the CPU started to work.But now it showed BIOS ROM CHECKSUM ERROR.I searched for that error and found that my CMOS battery must have stopped working.But i again started unplugging and checking all cables ,after 5-6 times of doing so,it started working again.

So i have come to the following conclusion,

Every time i restart the computer,it shows different errors (BIOS checksum error, just black screen and nothing happens, freezes when OS loads, or freezes at intel sign) or simply won't start up

So HELP ME!

My PC is 7 years old

Windows XP Professional SP3
Intel Pentium 4, 2.66Ghz, 1GB RAM.

 

[swilczak]

If you have two Ram modules try running it with each individual module and see what happens.

 

[DeathAndPain]

Forget the above. The cause is obvious: Your CMOS battery on your mainboard is depleted. Its voltage is right at the brink, so the system may be able to hold its CMOS data for a few minutes or so, but it is no longer reliable. You simply need to replace it (and redo any necessary BIOS settings afterwards). Remember to set the date and time afterwards, because you may experience all sorts of weird effects if you do not (such as Windows update failing with some weird mistake).

Mainboard batteries usually are of type CR2032. You should be able to get these on Ebay for 1-2 bucks. Or you can buy them in a local store fore somewhat more money. One of the most widespread battery types, so it should not be hard to obtain one. (You only need one.)

 

[swilczak]

Forget the above. The cause is obvious: Your CMOS battery on your mainboard is depleted. Its voltage is right at the brink, so the system may be able to hold its CMOS data for a few minutes or so, but it is no longer reliable. You simply need to replace it (and redo any necessary BIOS settings afterwards). Remember to set the date and time afterwards, because you may experience all sorts of weird effects if you do not (such as Windows update failing with some weird mistake).

Mainboard batteries usually are of type CR2032. You should be able to get these on Ebay for 1-2 bucks. Or you can buy them in a local store fore somewhat more money. One of the most widespread battery types, so it should not be hard to obtain one. (You only need one.)

He obviously needs a new battery but that would not cause the PC to freeze when the OS loads, so it sounds like there is also another problem.

 

[DeathAndPain]

He obviously needs a new battery but that would not cause the PC to freeze when the OS loads,

Oh, it easily can. Let him have his Windows installed with AHCI, but his BIOS defaults to IDE. Let his RAM only work with manually-adjusted settings which his PC vendor made 7 years in the past, and his BIOS improperly reads the SPD information and sets incorrect timings.

There are enough possible explanations. He will certainly need to fix his BIOS settings once he has a new battery in place.

 

[swilczak]

You could be right but I worked on about 30 different PC's in the past year that all had dead CMOS batteries and none of them would freeze when the OS starts.

 

[DeathAndPain]

I can only tell you that this is the point to start. You even had clear error messages pointing you towards it. CMOS settings getting lost are practically always the battery (unless you manually set the Clear CMOS jumper). Start there and replace the battery, then see whether and which problems remain.

 

[krv5vignesh]

Thank you both for answering.

I think the problem lies with CMOS battery,i reset that battery manually and my PC started without any problem.

 

[DeathAndPain]

That's what I kept telling you all the time. 😀