Computer Turns Off Randomly. Please Help!!!

[phaedrus06]

Hello,
This is my wife's laptop. It turns of randomly while she is on the computer although it appears to be more persitant while she plays World of Warcraft. It is a Toshiba Satillite P-35 Series, Intel Pentium 4 3.2GHz, 100 GB SATA, 1.37GB DDR 1 2700 (333MHz) RAM, 128MB ATI 9000 IGP built in, 17 in LCD, 120 Watt PSU at 19V, running Windows XP Home OS, and that should be all the important stuff. It is not a heating problem because the computer runs pretty cool, especially with the external extra fan it has. The suspect I thought about may be the PSU/Brick because it has been acting funny for a while. The computer runs fine on battery and doesn't need AC, but it is kind of annoying to have to every hour or so fix the issue. At first it was fine but then randomly the laptop would goto battery even though the AC was in. So the solution was to put pressure on the power tip and it worked ok (we stuck a book on top of it). Then we needed two books, and then I bought a metal clamp from the hardware store to clamp the end. Note that there are no external blemishes or nothing physically apparent to the observer which should lead one to see the tip is busted. Only the fact the AC shuts off.
Anyhow, even though I know a new PSU is in order I still don't that is the problem since it seems to happen with or without the AC power. After letting the computer sit for a while the computer will work fine on AC again but eventually the same thing happens again. Again I don't think heat is an issue because the computer is well below 45 degrees Centigrade. Usually it is around 37 to 40 degress or so. It just happens randomly is all and I have no clue why. Well, if anyone can offer assistance please do. Your help is always much appreciated. Thanks again.

-Fred