Computer will power on for 2-3 seconds and then shuts off. Please help!?

possibly the power supply has a faulty connection. it could be a problem as simple as you didnt plug the powersupply in all the way. try looking at your fans to make sure they can run properly. worst case, you contact the manufacturer

It would be difficult to check your bios settings if it only comes on for a couple of seconds, so how about you go get a known good power supply with enough amp and voltage to power your machine, hook it up and see if that fixes the problem. My bet is it will

just push the button 1 time dont hold it in or it will shut off . if the pc still goes off its a power supply problem cpu fan

You computer may have a malfunction in the cooling fan. It may be overheating. You'll have to take it to a computer shop and get a full diagnotic. You probably just need to get a new heat sink device. Also a possiblity is that you have a virus. Might need to reformat your hard drive

Yes my dear I know how, just follow these simple steps...

Click on "Start" in the bottom left corner of your screen...

Go to "Control Panel", click that...

Go to "Power Options", click that...

Where it says "turn off monitor" and "turn off hard disks" and "system Standby", click on the arrows on each one and make it say "never"...

Then go to the tab that says "Hibernate" and click that...

Un-check the box that says "Enable Hibernation"...

Make sure it is clear...

Then click on "Apply" and then on "Okay" to set your changes and go out...

You may have to restart your computer for those changes to take place and be set...

Veriry your CPU Fan or the BIOS settings.

Virus scan time!

check your CPU and/or power supply then try again