Does your video card support any other connection method that you can use to test the HDMI as possibly being the culprit, like DVI or VGA? HDMI can communicate two ways, as the video drivers
are loading your GPU will quickly turn your display off and on, normally we don't see this, sometimes we can. But if your monitor doesn't like this and reports a possible display issue in response to it your drivers might crash.
I had this issue when I used HDMI to plug into my HDTV, but not monitor because my HDTV didn't like when my GPU loaded drivers and "flashed" the display.