computer trouble

[adamhornsby]

I wonder if anyone can help, I seem to be having problems with my desktop again.
I was just transfering files to a memory stick, and the computer suddenly turned off back on and back off in loop. It wouldnt load, and wouldnt switch off when the button was pressed, so I turned it off at the mains then back on. I then try switching the computer on and it wouldnt fire up. Unplugged it and looked at the fuse, luckily enough we have a spare cable with the same fuse so I replaced it. Plugged it back in, pressed the power button, and the computer came back to life. It was working properly again, so I tried doing what I last tried doing and did the same thing again after a while. It keeps looping on and off, but this time shows a screen asking me what mode I want to start it in (Start Normally, Last Known Good and Safe Mode) I tried all 3 of these but no luck. As soon as I select one it reboots again. What is going on please? I have an incling its the PSU perhaps?

I was last on it on Monday and it was working fine, I've not installed or removed any hardware or software, apart from installing a game which I've had for ages and never caused any trouble, just seemed to happen out the blue

[spheric]

Your instincts are good... a PSU on the way out could well give this sort of problem. As windows boots, it will try to activate everything hooked up to the motherboard in turn, each drawing more power from the PSU.

You may want to go into the computer's BIOS to check temperatures... The behaviour may be consistent with overheating too.

If you have a spare PSU hanging around, a swap & test would be a quick way to diagnose the problem more reliably.

If it isn't the PSU, then its time to try booting safe mode with only the CPU (& fan), 1 stick of RAM and the hard disk (and graphics card if you dont have integrated graphics - use the integrated ones if you have both) and see if it boots, adding things one by one until you find your suspect

[adamhornsby]

Not that advanced at computers lol, but we're paying monthly insurance for it from PC WORLD, so maybe I'll book it in for a healthcheck, that might sound a better option perhaps?

[carlos007]

One of my systems does exactly the same thing,turned out to be a dodgy front usb connector every time I plugged in my memory stick all hell broke loose. Only use the one one the rear now with no problems. Unfortunately the pc is out of warranty now so just got to remmember not to use the front socket