Cpu fan works, power supply fan works why wont' computer come on?
Could be a number of reasons:
The CPu fan and the PSU fans will come on, even though the system is not working. There is a possibility that the CPU has blown, you can check this easily by (carefully) feeling the heatsink after it has been running a while. A dead CPU will not use power and therefore not heat up. If after say 10 minutes of running, the heatsink is clay cold, suspect the CPU. Replace with another one, spreading CPU grease on the top before putting the heatsink back on.
A blown CPU will usually be indicated bu there being NO beeps from the system (see below)
If the CPU appears to be generating heat, visually inspect the board, look for blown or blowing capacitors (the small cylinder like components) on the motherboard, any that are bulging or leaking a brown residue, or have blown, will render the motherboard inoperative.
If these appear ok (they still may be damaged), unplug all components except the hard drive, and ram and video card, see if the system then boots. If it does, proceed to re-installation of each in turn, until the faulty peripheral halts the boot.
Listen for any beeps as the ssytem switches on these beeps describe the type of problem
(repost if you hear any beeps)
Remove one stick of ram and try rebooting, if it works, suspect the ram module, try the other and see if that makes any difference.
Failing that, your last recourse is to power the system off, remove the bios battery, replace after 2 minutes and see if clearing the Cmos "unsticks" the computer.
After That, suspect the motherboard is dead.
Apr 25, 2011 |