HP Flatsceen monitor shuts down and turns off PC

I have an older HP flat screen bought used. The picture is fine but regardless of the

HD I connect to it, I walk away during a job, come back and everything is off.


I went through the power management settings in Win7 over and over.


At the monitor, I have no idea which buttons to press when in the on screen menus and if that is even the
problem.


The disturbing part is the monitor doesn't just go to sleep, it shuts down the PC altogether.


Just checking now, it seems display of the desktop is ok and stays on. But starting a program like
Handbkrake will take it down in 15 minutes or so. Repeating, I have fixed the power saver features to 'Never'repeatedly.


Using Open Hardware Monitor I don't see any high temps that would shut the thing down
early in a long handbrake job. It is possible a simple reinstall would fix such a strange problem?


The PC itself is an MSI with Athlon III and 4 Gb of memory.
System specs have always been adequate for what I do.


I'll start again tomorrow with some fail safe settings in the BIOS.

On the overnight, I could see that just leaving the desktop on caused no shut down.


Starting new today I ran the install disk for the drivers from MSI which I had neglected.


Set the priorty setting in Handbrake to lowest.


And from previous experience, I went into Win7 task manager and turned off two cores leaving one.
That's called the Affinity setting.



A quick check now and it's off again. I am now stumped.



One other thought: possibly select the Handbrake 32bit version rather than x64.


I'm running out of ideas. It may be something simple. This rig has been running for years.



I suppose I could run the Memcheck program to see what happens with that.


So two things: Handbrake non 64 version. Check memory.


Outside of this known application as problem, a different power supply does not seem to be needed.

When all else fails, change out the power supply. I've done that now with one off the shelf as a spare.
Everything is going for a while at least.


But the fact that the setup held the desktop with no problems put me off of checking the power supply.
I found anothew thread that directly discusses problems with Handbrake and shut down problems. It seems
that since it uses 100% of cpu and cores, others have experienced problems.




Handbrake keeps shutting off PC - Hardware Hangout - Neowin



But the other thing I wanted to mention was on those power supply testers. I thought of getting one
but the argument is the tester will give the same reading as my setup that displayed the desktop
ok but under load, shut down.


I'll mark this solved after some further runs.

Further testing of the bad power supply proves erroneous as well. I hooked it up
to a Biostar board, am running the same program recode job and neither shut down during a 6 hour process.


I can only surmise that the initial error had to be replugged or something to get it going.
I'm glad to have some spares again-- for the time being.


Thanks to those who answered.