Im trying to fix a computer for my son in law but it wont start up. Its an emachine 420 2.60 ghz intel celeron processor 80 gb hard drive. I noticed that when i switch it on i hear a clicking sound once from the processor and the fan is not moving. I hope i dont need a new processor. Can anyone help me with this problem, id be very grateful

Which fan isn't moving? We need to be fairly precise as to what is happening. I presume the keyboard lights don't flash and nothing appears on the screen.

The clicking could come from the speakers and be caused by a short propagating to the speakers. You mentioned one click not several.

If a fan isn't working, there may be a power problem rather than CPU. The PSU may have given out or there is a plain short on the motherboard.

So tell us more.

so , it won't turn on !why are you trying to fix it instead of a computer repair person who knows how to fix computers
!!!! when you say processor do you mean the actual cpu chip or the computer tower !

Im gonna stab at the problem being your power supply, emachines are great for having to replace them......but more details would be nice....

The fan on top of the processer is'nt moving. All the lights on the keyboard light up at the start when i switch the computer on

It appears that the BIOS functions are kicking in because of the keyboard lights and thismeans that the CPU is working.

However there may be an interlock between the CPU fan and the CPU such that if the fan isn't powered or doesn't work then the whole thing stalls. That might be complete bollox for your e-machine, but other PCs do this.

If the fan has a wire going to it perhaps you can find a way to check if it's got voltage (5V I think). You might check that the wire goes back to the distribution point on the motherboard. You could try another supply of the same voltage to the fan to check if it's the fan that's stuffed or the PSU.

That sort of slowly but surely thing.

or the fan could be bad ,can you spin it with your finger

Yes I can spin it with my finger. I forgot to mention that when i switch on the computer i dont need to use the start button on the front of the computer. If I hold the button in for a number of seconds to shut down the computer nothing happens , I have to switch off at the mains.

It might thus be that your short is at the front power button.

You've not been very clear about this, but reading between the lines, it seems that you can't turn the computer on nor off using the front button and that you rely on themains switch for all on/off functions.

Your PC needs professional repair IMHO.

try removing the wires that go to the switch from the motherboard and then bridge the pins oin the motherboard. if comp then works using the wall àplug / mains switch then the front switch onhte computer is faulty.
if the same fault appears then the controlling chip on motheboard / power sulpply is US
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