03 March 2015

Solving a funny hardware problem

A couple of days back my brother called up, saying the computer was behaving erratically.

It would boot, go up to the Operating System login screen and stop working. The monitor would go blank and switch off.

On restarting, it would beep three times and the monitor would go off. There was no power surge; no virus or any other possible reason for it to happen. The PC was running fine for more than two and a half years since we purchased it.


Remove the battery and put it back

I happened to remember what a corporate trainer had told me a long time back. He used to fix computer problems in his childhood and went on to become a freelancer and trainer. He said, 90% of computer hardware problems can be fixed just by removing the motherboard battery and putting it back (but his experience of 90% might not actually be the real 90% of problems that can occur).

I told my brother to do it, and he called back saying it worked! :-)

The big question of course was what went wrong? Maybe there was a memory leak in the motherboard software, maybe it was a bug that lay dormant a long time. But whatever it was, it got reset when the battery was removed.


Dust on RAM

Anyway, the problem was solved only temporarily and it recurred. This time, my brother noticed that it happened only when the CPU cabinet cover was kept closed. If kept open, the computer worked fine for a while. Suspecting that it might be a heating problem, I asked him to check if the CPU fan was working. It was, so the next culprit was the RAM. Turned out that the RAM was covered with dust, and removing it, cleaning it and placing it back solved the problem for good! :-)

It's likely that the RAM was getting over-heated because of the dust. Keeping the CPU cabinet cover open was allowing better air circulation.

This is definitely something you could try before calling a computer technician.


Beep sequence

Something I newly found out, is that you can make out what error happened, by listening to the beeps that happen when the computer starts up. For example, this is what Gigabyte listed on their FAQ:


What does BIOS beep sound mean?
       
AWARD BIOS
  • 1 short beep :System normal 
  • 2 short beep :CMOS Error 
  • 1 long beep and 1 short beep:Memory error 
  • 1 long beep and 2 short beep:Graphic card error 
  • 1 long beep and 3 short beep :AGP error
  • 1 long beep and 9 short beep :Memory Error 
  • Continuous long beep :Memory not correctly installed 
  • Continuous short beep :Power supply unit failed 

AMI BIOS
  • 1 short beep :Memory Error 
  • 2 short beep:Memory parity check error. 
  • 3 short beep :basic memory 64K address check error 
  • 4 short beep :Real Time Clock malfunction . 
  • 5 short beep :CPU error 
  • 6 short beep:Keyboard error 
  • 7 short beep :CPU interruption error 
  • 8 short beep:Graphic card error 
  • 9 short beep :Memory error 
  • 10 short beep :CMOS error 
  • 11 short beep :CPU cache memory malfunction

And do we expect a nice lady to say "Please leave a message after the beeps" :-)