Is there a way to determine if my PC is killing my monitors that doesn't involve killing another monitor?

Solution 1:

This is probably just random bad luck. This is more likely if both monitors are about the same age, and made by the same manufacturer. Also, the monitors failed in different ways.

If you suspect your AC power, your outlet tester will only show you whether or not your wall outlet is wired correctly. A multimeter will show you whether or not the AC line voltage is OK. To look for anything more advanced, such as surges, spikes, and dips, you will need a -very- expensive power line tester.

If you suspect the graphics card, you will want to look at the graphics card video output. To do this, you will need an oscilloscope instead of a multimeter.

Solution 2:

Once upon a time, I lost a monitor with a loud pop. I sent it off to be repaired. When it returned, I plugged it into the same computer and electrical outlet. "POW" again!

I checked the outlet with a tester and it showed bad. Since this was a commercial style 4-foot plugmold power strip (without any other circuitry such as surge protectors) and all the other outlets on it were OK, curiosity got the better of me and I opened the strip. Inside, even though the outlets were all oriented the same way, the hot and neutral lines were swapped for that one outlet (and "unswapped" for all the other outlets on each side of it).

This is what the interior of one looks like when viewed from the back of outlets. You can see how simple they are inside and can probably imagine how straightforward the manufacturing process is. Like me, you probably find it difficult to imagine how the mis-wiring occurred, especially considering the one I was using had heavier gauge, more rigid wiring than this apparently home-use model seems to have.

Solution 3:

It's unlikely to be the computer that's causing the dead monitors. The highest output from a vga port is 5 volts on pin 9. The pins for the red, blue and green data should be around 0.7 volts. If the computer was pushing more power through the port than this it probably would have instantly fried the monitor instead of working for another day/week/month.