desktop computer wont start at all

I would start with the power supply.

Next, would be to remove any modem or network cards.

Check to see if the CPU fan spins freely by hand. If not, the fan may have failed and the CPU itself may be dead.

If the power supply and CPU are fine, then it may be the motherboard itself.

Chas

Hi

Remove all that isn?t 100% neccessary for the computer to boot, also cables. That is everything except MoBo, CPU and Cooler (I think you don't have to have RAM i your computer for it to boot but im not totally sure). If it then works add a device at a time and you?ll find the problem.

But if it still dont work it can be either MoBo, CPU, (Cooler cant jam Bootup I think if its connected to the socket on MoBo??) or the Powersupply (PSU). You can test the PSU by taking the connector that goes from the PSU to the MoBo, unloosening it from MoBo and connect the Green cable with one of the Red cables on the same side of the middle of the connector. That will make the PSU boot if it?s working proberbly. If it still don work, your down to Mobo or CPU. Try borrowing a CPU from a friend. If it still isn't working its a Dark Side Mobo or the computergod who is at play.

Hope this helps. BTW, anybody know if theres like a database or similar with all these different possbilyties of boot up errors?)

May want to buy a another boot-up battery for the motherboard as you go thru the other suggestions especially if the comp is kinda old. Thier only a few bucks and often are the cause of a non-boot-up issues in older computers. Before tossing that motherboard I'd try it. By dead are you talking no beeps, no fans as well? If you get fans, lights then no boot up might be processor, or mother board, or battery. If no fans I'd look to power supply first.

Hi

I agree with TheChas as new style pc's will auto shutdown at CPU fan stoppage/ failure.

I hope it is a newer pc as replacement of CPU fan is where I start and then I slave a PS to it to check that sys.

fred