In 2012, sometime before Windows 8 was released (during the preview), I began getting BSOD's during the install process. it would take a few attempts to get the install to go through, then all would be fine. Once Windows 8 was released on promo to the everyone, I upgraded (actually cleaned installed) the OS, bypassing the upgrade & creating an ISO. I then used the Windows 7 USB/DVD download tool to create a bootable Flash drive & also a DVD.
No matter which type I used, the initial part of the install would go through (as with the previews), then there would be a reboot. It was always around the 65% (or so) mark that the PC would BSOD. It took 6-7 attempts to get the install to take place. to go all the way through. Had to reset the PC a couple of times & the same would happen, requiring more clean installs, where the same thing would happen & it took more attempts for the install to complete. There are no longer any Event Logs, but the only device that wouldn't work was the wireless card (Atheros AR5007EG), which I disabled in the Device Manager.
After a few months of frustration with Windows 8.1 Pro w/Media Center on this PC, I reinstalled the original OS (Windows 7 Home Premium x64) & for a bit, the issue went away. Sometime after this, I happened to be moving some things around in my workstation desk cabinet, where the built in power is, plus the UPS that was being used. For that purpose, the UPS was fine & still is used to backup the modem/router, plus my backup devices, to make room to plug another device (not to the UPS). It was then, that compared to the other two notebook type PSU's under there, that the one for the HP was very hot, after moderate use (Web browsing), too hot to hold comfortable.
Finally, one day the PC would no longer boot. I managed to get it to a few more times, to run diagnostic tests, but it would always crash. During this time, the PSU would be just as hot & was no longer plugged into the UPS. Then one day, it would no longer boot, no matter what I tried. However the power light still comes on in the center of the button & the green light where the PSU still comes on. Also, the CPU is getting power, because it gets warm & the fan power cycles normally. The HDD is spinning. The notebook style optical drive has been removed & am using it as a portable for other devices, so that can be removed from the equation. The CMOS battery has been replaced.
What it won't do is show any graphics (even the HP splash screen), nor will actually boot, or recognize any USB devices plugged in, keyboard/mouse, or Flash drives. If it were, the light on these would blink. This is the PC in question. I've tried to get it to boot on three different outlets, all were in separate areas of the home.
Now, what I have done to test the PSU is this (as seen on YouTube video). Using a multimeter. placed the negative lead on the outer part of the connector & the positive lead to the center pin. Consistently get voltage reading of around 16.23V. This is over 2 Volts less than the 18.5 as what the specs on the label shows (genuine HP PA-1121-42HQ). As another test, though I don't know if this means anything, placed the negative lead as usual, to the outer portion of the connector & the positive directly to the inner wall of the connector & am getting a 19.94V reading. That would be nearly 1.5V extra, if that means anything.
If this PC were 10 years old, I wouldn't be wasting my time over this. However, it was less than 4 years old when the PSU was overheating & tapped out. I paid around $600 for the PC, averaged over 4 years, that's a poor ROI (return on investment) at $150/year. Windows 7 is still being supported for awhile, so if a new PSU will make it run, I would like to go for it. At the time, cannot find any used ones to test with, so would have to chance $20-25 to see it it's the answer.
Now, before I spend any money, is there the chance that other components may be bad? I know that there are no guarantees, but am hoping that someone else has experienced similar issues & can provide feedback. Did I perform the test right (negative to outer sleeve, positive to center copper pin)? Too, there are no bulging capacitors or burned spots on the MB.
And should the 18.5V be consistent, as in that range all the time? I'm not an electrical expert, however it's my understanding that it's the amps that varies, the more the demand, the more amps needed & will be provided up to the max of the PSU, which is 6.5 Amps.
The PSU is 120W. My belief is that it was inadequate for the PC as shipped, though it's mostly notebook components, it has a 3'5" SATA ll HDD, along with an 18.5" monitor. I've seen notebooks w/out a large monitor & regular notebook HDD (or SSD) with larger wattage PSU's than this (150-180W). And slightly different business models of the MS200 series ships with a 150W PSU.
I just don't want to pour a lot of cash into what may be a damaged PC from a bad PSU, but would take the chance if there's reasonable belief that it may run. That is, PSU only. I'm not spending cash to replace the MB or other components.
And if there are other tests that I can perform with a multimeter to test for damage, I'm all ears.
I've provided as much detail as I can remember, has been since late last year since it last ran.
Thanks for any advice or assistance provided.