Follow the above advice except for the movement of the fans.
If they move the Power Supply could be bad I had one recently the very first Antec PS that has sort of died without good reason, It would turn on once in 20 to 30 attempts and was a nightmare to track down as I've used thousands of these PS and never had one fail so I didn't think to look at that part of the Computer I just reasoned that it was the M'Board not sending the signal to keep the PS running. With an ATX PS it should run for a fraction of a second and if it doesn't get the proper signal from the M'Board it will stop. What can sometimes happen is that the control circuitry will fail to accept the signal from the M'Board and turn off the PS.
If this has never worked from day 1 then dismantle it and try running it on the bench with everything bare if it works then the Case is at fault and I've seen quite a few that had stopped computers running for no reason that I could see but the moment that a working system was fitted the units failed to start. Antec has a PS tester that you can buy really cheaply and is useful but if you have a faulty PS it can be very misleading as well so you can mistakenly believe hat the PS is working fine when it isn't and waste hours attempting to fix something that isn't broken.
To test out of the case all you need is the Box that the M'Board came in and sit the M'Board with the CPU & Heat Sink fitted along with the RAM and Video Card and plug in the PS if you don't have a spare switch you can use a metal screwdriver to short out the 2 pins to start the unit running these are the same pins that the front On switch would normally connect to and you don't need to keep the pins shorted just a quick touch will be enough.
Col
