Computers (pc) - auto switch-on?

[Barquentine]

How many different locations in my PC are there where one could set a clock and an option to make the pc turn itself on every night at 3am?

Not that I want it to. I bought the machine from a guy who builds them in his basement. Trouble is, at 3am every night it switches itself on (unless I turn the mains supply off).

I have tried many routes to try and find how it is doing this.

If any savvy IT person out there could list all the possible clock/type locations maybe I could see if I missed one. Thanks.

[ChuckFickens]

Only one place, In the BIOS

When you first turn it on there will be message saying something like "press XX to enter setup"

Press the button indicated (you only have a couple of seconds, if you see the windows logo it's too late) and have a look for a auto power on setting.

common keys that you might need to press to get into the BIOS are F1, F2, F9, F10 and Delete.