My monitor has power cause it has a light there, and my sound has a light there too so it isn't the power, but when i press the power button my computer doesn't turn on, it doesn't even have that beep sound going, and and last time i check , my laser mouse doesnt have that red light at the bottom like it use to. Can anyone help me? My computer is P4, 512 RAMs, and ill get more information later, can anyone tell me the common cause that many people are having with my problem too?

What did you do before this happened? Hard to say what it could be, you have to explain step by step what exactly happened and how.

Well I turned it off by going into the start > turn off computer > shutdown step then the next day i press the power button it my computer wont turn on.

Well when something like this happens usually you have to check every part separately in another system or vice versa. Cause it could really be anything.

You can always try clearing the cmos, this is how.. remove the battery and all power connections going from the power supply to the motherboard, wait 1 or 2 min..replace the connections and battery, making sure the battery is replaced the same way it was.

I doubt that will work but it's worth a shot.

If that don't work and you don't have other parts or another system to try your parts in, i would just bring it to get fixed at some shop where they can do that for you. Then you'll know what part is broken and you can replace it.

hey maybe you can change your front side bus to 100 if you have jumpers on your motherboard use the manual to find out, this will reduce you mhz but if windows boots again then you can place the jumpers to their original position. maybe I'm wrong but this might be worth a shot.
gigz

Bios reset might help, but more likely its a hardware failure.

Sounds like somthings making your coputer shortcircuit. A broken part or a screw dropped on the MB.

Was there a thunder or some "nature" phenomenal at night? Im putting my bets on the Power supply. Normaly even if theres a broken part or even a shorting, the PSU fan spins a couple of times in the boot. You should allso check if the cable coming out of the power button is connected.

Do you live alone or is there a possibility of someone tampering with the compute while you are a sleep, away from the room, etc? Someone young and restless?