Toshiba Laptop Randomly Shutting Down

I've got a Toshiba Satellite A105-4384. I am running out of possible solutions and in need of extra help as to what I should do next. So let me get to the rundown of things. The laptop will run fine but it will just shut off at random as if the power chorde was pulled out. There is no battery anymore since it can no longer hold a charge. The random outtages started about 7 months ago and they have been getting more frequent as of recently. I have taken the laptop apart and have reseated everything, dusted out the insides thoroughly including the fan and heatsink. I then took the time to use ram from another system just in case the Ram was bad. Problem persisted. So then I ran HDTune and one other HDD diagnostics and it had a lot of bad sectors and put in a new hard drive reinstalled Win XP and all that jazz. After that the problem persists. So, I try running a multimeter on both the AC adapter and internal DC jack, so I replaced AC adapter since the numbers weren't consistant, problem still persists. Then I went ahead and added new thermal paste to the heatsink over the CPU. Problem still persists. So I don't know what to do from here honestly. So any ideas/advice would be helpful. Thanks in advance. If it can help at all here's some specs of this particular model.

Operating System
MS Windows XP Media Center Edition Professional 32-bit SP3

CPU
Intel Mobile Core 2 Duo T5500 @ 1.66GHz 114 °F
Merom 65nm Technology

RAM
2.00 GB Single-Channel DDR2 @ 332MHz (5-5-5-15)

Motherboard
Intel Corporation MPAD-MSAE Customer Reference Boards (U1) 114 °F
Graphics
Default Monitor (1280x800@60Hz)
Mobile Intel(R) 945GM Express Chipset Family
Mobile Intel(R) 945GM Express Chipset Family

Hard Drives
313GB Western Digital WDC WD3200BEVT-00A0RT0 (SATA) 112 °F

Optical Drives
MATSHITA DVD-RAM UJ-841S
ELBY CLONEDRIVE SCSI CdRom Device

Audio
Realtek High Definition Audio

 

Thank you for the help. I think your right that the motherboard is failing. I tried using a friends battery for the same model. Still was shutting off so now I know it wasnt the power supply issue because the battery was charged and the power chorde plugged in. So I guess I'll be replacing the motherboard. I have noticed something else peculiar is that it has a higher rate of shutting off when I do things that seems graphics intensive such as Flash videos, or when Im working with Blender or trying to run 3D Games it normally shut off after 5 minutes everytime. I can watch other types of videos such as MP4 or MKV files for hours, no problem. I can also play 2D games as well for hours before it will randomly crash. So in trying to discover what the problem is just because Im trying to learn, would it be safe to say that it is the graphics chipset on the motherboard causing the problem? The heatsink on the graphics chipset on the board is stand alone and has no way of cooling. So I wonder if a possibly good fix would be to try and get a custom heat sink that attaches to the other heatsink on the processor to cool it off would help.

 

So I've set up WinXP to make a log via the System - Advancd - Startup and Recovery tab so far its turned off 3 times since then. I don't have any logs thus far in any of the locations recommended. I don't recieve any BSOD before it shuts off so I don't think a log gets created. Should I try anything else?

 

Yes I did check the event view a few days ago and nothing comes up in the event viewer except that it started up. It doesn't note any of the random shut downs. Main power is all I've really got. I've tried running off the battery, the battery doesn't have enough life for me to tell if it will happen with that power source as well. Also the random shut offs have gotten worse, including breaking the record for shutting off at random (23 times within 2 hours) so I went ahead and pulled the hard drive out. So I run live CDs/OSes on usb on it for now.

 

Will Windows stay running on any known-good hard drive plugged directly into the motherboard?

If no, you probably need a new motherboard.

(Software can't fix failing/broken hardware).