PC dead no post

[Dave10]

Hi everyone its been a long time since I visited you all but I find I need help.I rebuilt a pc for a group I belong to about 6 months ago and all went well it's been running 24 hours a day since then in a unheated astronomical observatory then last week one of our members went down to check if all was well and the pc seemed to have crashed ( outside temp was minus 4)he brought it back for me to look at.There is no post beep I have swapped out psu,graphics card,hard drive,ram to no avail I then stripped it to bare essentials disconnecting everything not necessary still no joy for some reason I then tried heating the innards with a hair drier and lo it fires up ok till it cools down then everything freezes again,reheat ok for 10 min or so then crash again.There are no signs of damp on the mother board (removed) has anyone any suggestions.Regards Dave

 

[jknichols]

Sounds like either a bad solder joint or a hairline crack somewhere on the motherboard - heat it an the metal expands enough to push together, cool it and the metal shrinks and opens the connection back up.

 

[Dave10]

sorted 3rd graphics card ! and it works ,the other cards all work in a different machine so explain that one.Its fixed that's all that matters Regards Dave