Computer won't stay on...

B'stard

My computer won't stay on after I switch it on. It starts up, I can see the fan's on the graphics card and processor spin up, but then the computer re-boots itself. I get no post text on the monitor.
I've disconnected all the devices from the back of the computer, I've also disconnected the hard drive but its made no difference.

Any ideas?

Lokolo

Do you get any beeps from the PC?

Does the monitor turn on? (even if it displays nothing, if its on standby, it should recongise computer and auto turn on)

jaydeeuk1

I'd check PSU first, then look at poss shorting, damaged power button

B'stard

Monitor light comes on, but then goes off when the pc re-boots.

Decyfa

B'stard wrote: »

My computer won't stay on after I switch it on. It starts up, I can see the fan's on the graphics card and processor spin up, but then the computer re-boots itself. I get no post text on the monitor.
I've disconnected all the devices from the back of the computer, I've also disconnected the hard drive but its made no difference.

Any ideas?

First of all re-connect the hard-drive.. Its more then likely your PSU is not powerful enough to run your pc. Post up the specs inc make n model of your pc and it'll be easier to help.

turbobob

Is this something thats 'just happened' or did you change anything before it stopped working?

Lokolo

I had this problem when my CPU wasn't plugged into the power socket on the motherboard.

Lil306

Lokolo wrote: »

I had this problem when my CPU wasn't plugged into the power socket on the motherboard.

I'll second this if you get a blank screen your power socket for CPU (4-pin) may not be connected

I'd like to suggest something else, take the motherboard out of the case and put it on a cardboard box (or something non-conductive) (not the floor!!) then try testing it, it's possible the motherboard is shorting out, if it shorts it can reboot the PC.

The best way to test the motherboard is by disconnecting EVERYTHING and using the onboard VGA. Only remaining components should be CPU, Heatsink and RAM. Nothing else should be connected until you know the motherboard works.

turbobob

Yes its not going to do much without the CPU in the socket :rotfl:

I think you meant you forgot to plug in the 12v CPU power connector.

heather_p03

My PC does something similar but this started after my son 'clicked on something' last night. That's my task for today! I think he's definitely introduced something nasty.
He panicked when things started to go wrong and switched the PC off without calling me first.
If anyone has any suggestions please?
Thanks.

totalsolutions

HI, try going into the Bios, Hint - press del or F2 or F8 at power up. See if it holds power in the Bios state. If it does use the F8 key at enter the "Safe Mode" again see if it stays on.
In safe mode run malwarebyte or hijack this programs.