Sony VAIO keeps shutting down, maybe CPU problems?

Hello all:

I am really hoping that you guys can help me with this problem that my grilfriend's Sony VAIO is having. I will try and be a specific as I can be describe. I am looking for any software that can diagnose the problem. so here goes.

The model of the laptop is VGN-NW270D. The problem is that it shuts down randomly it seems. The first time after the computer being off for a while, it shuts down after between 0.5-1 hours being on. If it is turned back on, the time seems to decrease pretty quickly, like minutes after coming on. If it is left off for a good while and turned back in, it seems to repeat.

Some stuff I have tried was booting into a Linux live disc, and the problem still happened, so I don't know if it is some kind of virus. Looking around online, some people talking about those same symptoms and it being a problem with the voltage regulator. I have also opened the thing up and there doesn't seem to be any dust at all. Everything looks pretty clean.

So does anyone know what could be going on? Is there any software I could run during that first hour or so it can stay on? I am pretty good with electronics and computer, but I am at a loss. Anything would be greatly appreciated and if there is anything else you might need to know, please don't hesitate to ask. I have pictures upload to my public Dropbox, if anyone wants to take a look I will post the URLs. Thanks!

Thanks!

Have you been testing on battery or AC power? What's the battery state when it shuts down?
Have you been monitoring the system temps?

Try HWMonitor
http://www.cpuid.com/softwares/hwmonitor.html

How about testing with the battery detached and running only on AC power.
That will help eliminate one possible variable.

For checking the battery - try Battery Care: http://batterycare.net/en/index.html

Thanks for all the replies everyone. I can't do any of those tests cause it won't stay on long enough for me to get into Windows. Just shuts off. This happens on both AC power and just the battery. Looks like it isn't worth very much now. Haha.

Yeah...I think I will try that. I might just stick it all back together and bring it to a professional. Haha.

So i went into the bios and there was nothing there list you said. I decided to take it apart again and I did notice something: The part where the heat sink is over the chip, the thermal paste is really hard, like not even a paste anymore. could it be that the sink just isn't absorbing the heat from the cpu?

Hi I was wondering if you managed to find the source of the problem? I have a Sony vaio vgn nw11 and which was fine up until yesterday when it went on the blink. Keeps powering off, then restarting all hardware seems to be nice and tight I.e hdd and ram. Some times I get to load windows sometimes not very frustrating... Any advice?