kingsmash82 :
I'm Ismail I've 21 age of birth and am IT Technician
My PC is Dell Optiplex Gx280 does not start when i switch on the fan running high speed but does not boot and can't Display anymore!!!
It can either mean something is disconnected inside your PC or your motherboard is malfunctioning.
I would suggest that you open your PC WHILE IT IS DISCONNECTED FROM ELECTRICITY!, and check for loose/disconnected cables. Make sure all cables and components are well inserted in place including your VGA.
Let me know how that works out in order to further help you,
*** All my answers and posts are merely suggestions which you perform at your own attempt, risk, and responsibility.