Random Power Shutdown.

My specs are

Gigabyte G or S series motherboard
3.06gHz Intel Pentium 4 Processor
2GB Ram DDR2
660GB HDD
512MB Nvidia GeForce 8600GT video card

Now the problem. About two months ago, i performed a few upgrades, adding an extra 500GB HDD, the graphics card and an extra 1GB Ram. Not long after, it started to randomly shut down on startup. In order for me to fix it, i would have to turn the system off at the wall, get behind my computer (not easy at my height), unplug the power cord, plug it back in, then turn it all back on. I figured that my power cord, since i had no reason to believe differently. So i got myself my backup power cord, and used it instead, and it stopped for a few weeks until the other day. Now the problem has returned with a vengeance. Today it has happened 3 times, but it has been happening in applications. I did a virus / spyware scan, and as i had expected, it was clean. Now when i added my graphics card, due to the size, there was a lot of difficulty in inserting it. We had to move cords, move the HDD and such to get it in. My theory is that during the procedure of inserting my Graphics Card, one of the power supply cords connecting the Power socket and the motherboard was dislodged, and this is the cause of it. It would explain why the problem is prevalent on startup, but is there something else that could cause it. So far i have investigated

*Dust in the computer - there is none.
*overheating - this doesn't appear to be the problem. There is no heat on the system, and it apparently works fine for 6 hour sessions, and such
*Overpowering - checked the power figures and the changes after my upgrade, and it still shouldn't be causing it.

By the way, i bought the computer new 9 months ago.

Thanks in advance

 

my old gateway pc used to randomily do a hard reboot for no reason even though i was pushing it's psu to the limit (video card,dvd burner etc) even though you said it sgouldn't be that it might be your push your psu to it's limit.

 

Hi, random reboots can sometimes be caused by a malware called Element\boot.exe. Spybot Search and Destroy can find it and remove it .