Uncrashing a PC by diagnostics

Unfortunately I could not say NO when a friend asked me to take a look why his PC crashes with a hung and sometimes a blank screen. When something like this happens, for sure it is a hardware problem. To reach the ground of the problem I can advise you to follow my steps to get to the cause quickly.

1. First of all monitor the fans and temperatures using tools like SpeedFan and make sure everything keeps in a normal range. Disable the screensaver and do something memory and CPU expensive like SETI. When the computer crashes and the last view shows values out of range, then replace the fans by better ones and in case of CPU overheating, remove and renew the heatsink paste. Maybe it got too dry and lost its thermal conductivity.
2. 

   Test the memory bars each by each. Take all out except for one and run a memory tester booting from CD or a USB stick.

   Remove the power chord when doing that! If you still leave it in, the power adapter gives some voltage to the mainboard and a short circuit will happen fore sure.

   When the test is completed and no errors are shown, that bar is ok. Turn off, replace by the next one and so on. Do not use a corrupted bar anymore.

   • If no error occured at all, put all bars in and run the test again. When now an error is displayed, the slot may be dirty or corrupted!
3. 

   Do a full harddrive surface scan. This is neccessary because Windows uses a pagefile to supply virtual memory. If the sectors are bad at this area, data is written, but not read correctly and placed into the RAM without any further validation. With a surface scan Windows will mark that bad sectors not to use them again. Go to the workplace, rightclick your main drive (mostly C:) and select Extras then Check drive and Surface scan. This may take a very long time depending on your harddrive speed and storage amount.