DEAD COMPUTER PC
Disconnect all devices from the power supply EXCEPT the motherboard
Remove any extra cards including video etc.(plug monitor into the on-board)
If the PSU fan does not spin then time for repair / replace
If you hear any beeps these can indicate where the fault is.
either of these sites below will help you further with that
Beep codes Pc
More beep codesPower up the PC and see if the fans are working.
If not then double check the power connections to the board.
If you still have no fans it is time to suspect the power supply as the probable cause.
If the fans worked then you should have gotten a display which told you there was an error and offering you a chance to go into the BIOS. ignore it and shut down the PC.
Now connect one drive only and boot again.
Repeat that until you identify the component that is giving you a problem.
Once you find the problem then remove or disconnect and carry on with the rest to see if another component might also cause a problem
If there is only one problem device then you may want to investigate that device further, Unless you don't mind replacing it
I take the view that having disconnected everything else you have at least saved those components that are not connected. There is a SLIM chance that re-connecting to the motherboard can cause damage.
Most power supplies will however fail to deliver ANY voltage to a motherboard if it is fried. It is a risk I would take and have done on many occasions if there has not been a spare power supply yo hand.
To date I have not fried one single board
Local PC shops have a small special tester so you could take out the supply and take it to be tested. It is quick and easy for them to do and takes only a few seconds if they have a PSU tester.
Bob
EXMOD
It would be very decent of you to consider the quality of our experts answers and judge them accordingly as you pass through FixYa.
Thank you