Laptop Mobo dead/dying?

[Windows98]

Hello everyone, it has been a very long time!
I have a question for someone who works on laptops.. I am a desktop kind of guy, I will try to post short bullets instead of long paragraphs.

Laptop is a Toshiba Satellite A665-S6065 Bios v 2.30
OS: Windows 7 Ultimate
Specs: i7-720QM
Nvidia 330M
8GB DDR3 memory
500GB 5200 RPM Hitachi drive


June 2013:
While doing some gaming and memory intensive applications the laptop would BSOD. I would get a Blue screen at least once or twice a week.
Ran memtest86 and Windows memory diagnostic everything checked out.

July 2013
Went to toshiba's website and update/ re-install all drivers for the computer.
Laptop starts to act worst. Blue screen still happening, but now laptop would shut itself off randomly. (As in your in the middle of something and then the laptop completely powers off. If to say something overheated. This is just surfing the web.
Run CPU stress test using prime95 - nothing happens (2 hrs)
Run Video stress test using future mark - nothing happens(1 hr)
Rerun memtest and windows memory diagnostic - all pass (after 8 hours)
Run segate HD tools for windows - all ok
Windows is telling me it has problem with virtual memory allocation on my laptop. (Page file set to automatic)
Goes do something which requires a bit of everything( web browser with multiple tabs, loading youtube video... crashes..)

August 2013
Go gets BSOD screen reader and see what is causing BSOD I see pagefile.sys as a problem. Wlan.dll, realteck,dll all errors seems to have ntoskrnl.exe error
Goes get window 7 CD insert and repair windows - after repair try running something that would crash my laptop. Opera with 20 tabs open and then try running a browser based flash game. 1 minute later BSOD,
Use command prompt and tried sfc /scannow. Everything checked out ok.
Went to My Computer and scheduled a disc check. Also checking free space while it is running. - Comes back and find that the laptop shut itself off.

Turns laptop back on, and enter hard drive password. - Laptop shuts off after 10 sec. Try again, does the same thing....

Go remove 1 memory module - try again laptop shuts off after 10 sec.
Swap other memory module - laptop shuts off after 10 sec.
Swap module slots - laptop shuts off after 10 sec.
Go into System bios and not do anything.... - laptop shuts off after 10 sec.
Remove Hard drive and let the computer sit in the BIOS - laptop shuts off after 10 sec.
remove all memory module - computer receives power but nothing on screen and no beeps.

Thinking something might be overheating. I spent all morning 11:00 pm 8-13-2013 to 4:30 am 8-14-2013 Took the motherboard out and looked for burnt or something that might show what is wrong. Either hardware must have  overheated and broke or capacitor gone bad. Cleaned the CPU fan and heat sink. By the way, OEM likes to smother there components with thermal paste. When I took the heat sink out and saw all the thermal paste I was like *censored*..
Cleaned and looked at CPU and GPU and did not see any burn marks or any indication that heat was a major issue.

Re-apply thermal paste put everything back together and tried the laptop this afternoon. I put in laptop password and 15 sec laptop shuts itself off again.
Try sitting in the bios.. laptop again shuts itself off.

This laptop HD is encrypted with TrueCrypt. The laptop was showing signs of problems with BSOD and I was going to decrypt the hard drive after checkdsk. It crashed somewhere in checkdsk and now the laptop won't stay on long enough to even log into windows.

The laptop does come on still. It will show the Bios welcome screen and then ask for laptop password. As soon as you enter it in or just let it sit for a few sec it would turn itself off.
The same thing goes just sitting in the BIOS not doing anything.
Try using Ubuntu Live CD. - Shuts off while checking system hardware.

Power connector is fine, I also tried running on a fully charged battery only and same problem.

If someone who has more experience with laptops knows what I should look for on the motherboard or what else I can try to test let me know. I am disappointing that this laptop only lasted me 3 years

Lucky I have MOST things backed up on the Home storage server.... though I probably should have a backup to the backup...

[DaveLembke]

Very strange.... so it was 10 seconds exactly and it would shut down. You opened the laptop and added new thermal compound and now its shanged to 15 seconds exactly?

Only thing I see that hasnt been done is trying to run the laptop without the battery installed just off of wall power.

Worst thing is that the warranty is likely void by opening it up if it still had one active.

I heard of Toshiba suggesting a flash for their laptops to throttle them down to relieve failures, but I dont believe the issue is for the Core i7. I think it was mainly with the AMD CPU's running too hot.

On simple google search it looks like this model may have heat issues, although with what you did it should have cured it: http://www.google.com/#bav=on.2,or.&fp=577560816760f5b2&q=toshiba+satellite+a665-s6065+overheat

Toshiba forums have lots of people angry with issues with the Core i7's in Satellite model, but claiming that the Core i5's are more reliable.

[Windows98]

Well, I took it apart again and double checked everything..

Looks like a sensor might be bad somewhere.

I only noticed this when the room was quiet.

When you first turn it on, the fan speed is on slow since nothing is really warmed up yet. If you just let it sit on the password screen about 10 seconds in you start hearing the fans suddenly go full blast like something is overheating and it is trying to quickly cool it. After a few seconds it shuts off.

If you turn it on again immediately it does the same thing.. Slow speed for a few seconds then the fan runs full blast like something is overheating. I even try putting next to a window fan with air directly on the laptop.. same problem

The biggest question is what is wrong.

If it is the CPU pretty expensive to replace but least problematic.. plus I might as well upgrade it.

If it is the chip set, then a new motherboard needs to be ordered and that can get expensive, if the video card is bad new motherboard since it is soldered on.. Plus I got to get the right motherboard because it comes in so many configurations... integrated graphics with i3-i5 clarksfield or  i7 gets the 310M, 330M or 540M.. LED back lit keyboard versions.. (sigh)

I guess if their is an easy way to figure out which sensor is bad and see if it can be patched up it would be easier. I looked at all the soldering and they look ok. I even cleaned the rubber pieces, they are light blue and feels like play dough that covers some chips that connect to the heats ink.

http://www.sparepartswarehouse.com/Toshiba,Satellite,A665-S6065,PSAW3U-03Y001,Laptop,System-Boards.aspx <- Big ouch since buying a new motherboard is basically almost half of what I paid for it when new 3 years ago!

What the inside of the laptop looks like: http://www.irisvista.com/tech/laptops/Toshiba-Satellite-A665-A660/laptop-disassembly-3.htm

Also can't tell if a video card is already soldered on or you have to buy your own video card and install it...

When it was new: $900 on newegg.

I currently have it running on bare parts. power connector connected, CPU with heat sink connected and then memory. No Hard drive connected. I try touching some parts to see if something is getting hot fast enough to trigger it.. Nothing. No fan since the fan is just a mini fan blower that basically blows air to cool it and its not really attached to anything.

To bad the BIOS doesn't show any voltage or temps..

[patio]

Speccy will report voltages and Temps...still Free.

Good to seeya again...long time.   

[Computer_Commando]

I suspect the heatpipe (shown in Step 27) has lost it's cooling fluid.
http://hardforum.com/showthread.php?t=1663389