Hi,
I'm not sure if this is relevant, but I am using 2 monitors, the HP with the problem is used as the secondary monitor (in Windows 7), which I use rotated to the vertical position. I has been working fine for years until a few weeks ago.
When I boot up the PC in the morning and turn on both monitors, they always turn on fine. The problem happens after they go into suspended state; when I move the mouse to "reawake" them, the HP monitor turns on for about 1 second, and then turns off (although the power button remains blue, as if it were on). I then try to turn the monitor off, and on again, and the same happens, the screen turns on for 1 second and then off. After I do this some times, it eventually stays on, but it seems that its taking more and more attempts (last time I had to turn it off and on about 10 times).
Any ideia on what could be happening here? Thanks in advance!