It powers up but screen is blank. Fan is blowing hard.

..hi there!..try to check your RAM ( memory )..clean them..if the issue still occurs, try to checked or replace your power supply with a good one..i hope it helps!..^_^..

there can be a lot of reasons for not starting.
Power supply as above
HD failure
MBR file corrupt
Virus
corrupt files on HD
non detection of HD (motherboard fault, hd fault, virus..)
Video failure (either connections as above, card failure on motherboard or card)
do you get any bleeps as it tries to start? if so Google start up bleeps and the number of them to find where the fault lies;
Other likely possibles are keyboard not connected
Dead screen
broken cables
even leaving a dvd with a boot on it in the drive!!

best of luck
M

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