My first computer question

[SmithFamilyDesigns]

Alright, quick comp specs:
MSI CR600 (Hate these things)
C2D t4400, 4Gb pc6400, 320 WD blue label, GeForce 8200M G

Originally came in because it would not power on; no post, no backlight power, the power LED lit and that was it. After EXTENSIVE tinkering, I have now got the computer to turn on. Problem now is that it will randomly shut off. No warning, no nothing, just off.

What I have done so far:
To get the computer powering back on, I had to change the CPU (old one showed serious signs of heat damage), replace the fan and clean the vents. It was running Vista HP x86 SP2 and would do the random shut downs with no warning. Running PC Wizard showed all temps in normal range (100F - 125F) for CPU & GPU.
Whenever I try to boot the computer to QTP for hardware testing, it will always shut itself off somewhere different in the test. I have replaced both ram sticks (also trying 1 stick in different slots), changed the hard drive, tried yet ANOTHER processor, disconnected wifi, USB ports, webcam, and hard drive and it will still always reboot during a HW test. I have also done all of this with different combos of battery/uni power adaptor/factory power adaptor.
For S&G's, I put in a new HDD, installed Win7x64 and it showed the same temps as vista did (few degrees difference) but still shuts down with no warning.

My question to you TN, is it the motherboard? The only thing that I think I haven't tried (depending on posts here) is the actual power switch board, but to buy one is too much for testing and this one seems fine. Anything else I should try or should I toss this in the heap for spare parts/scrap?

Edit: Forgot, I did download the newest bios and flashed that. In the process, after a reboot, I shut down and reset the bios (battery out, cmos battery out, unplugged, hold down power button for 30 seconds) and that didn't make a bit of difference.

 

[Jeffreynya]

The Button board could be causing the issue, have seen it a lot on hp's. You may also want to disconnect the display and just plug in a monitor and see what happens. I have seen displays cause shutdowns, but its rare.

 

[SmithFamilyDesigns]

So here's an update:

I removed the power board and jumped the ribbon cable to rule out the power board. Still shut down after that.

After HOURS of messing with it, I noticed a pattern; whenever I touched the left side of the palmrest below the keyboard, it would shut off. It was still doing it without that, but it would always shut down when I touched it there. After completely disassembling it again, I noticed that the heat shield under the palm rest seemed to be laying directly on the mobo with no protection. I took some of the black plastic sheeting that used to protect pcb's from hard drives and put it over the heat shield. Guess what... It worked! Apparently the heat shield was shorting out the mobo after a lot of use and the palmrest started sagging a little.

To anyone wondering why I've put this much time into this computer, it's because it's mine now. I offered the guy $30 credit towards a new laptop for it and I would've made my money back just off parts. But I'm a bit obsessive and HAD to know what was wrong with it. Now I do!

 

[DavidF]

Nice work, you can't let an inanimate object get the upper hand.
Through similar circumstances I own the MSI VR6 that I'm using to type this post.
It's showing similar tendancies to your description although a little more random.
Tomorrow it'll be arse up on the bench with particular attention to the problems you've described

 

[joydivision]

Sounds like a very poor design. That should have never been allowed to have happened.

 

[DavidF]

Yup it may well be poor design, at least it's easily rectified unlike HP's DV series and doesn't become landfill a month out of warranty.

 

[SmithFamilyDesigns]

Nice work, you can't let an inanimate object get the upper hand.
Through similar circumstances I own the MSI VR6 that I'm using to type this post.
It's showing similar tendancies to your description although a little more random.
Tomorrow it'll be arse up on the bench with particular attention to the problems you've described

Definitely worth it if you have the time. I'm actually writing this from that computer now. It's been running since I posted yesterday with no issues.