I've only ever used monitors driven by a PC playing video, not from some other video source, but for those scenarios I've not had any trouble. The problem with

I've only ever used monitors driven by a PC playing video, not from some other video source, but for those scenarios I've not had any trouble. The problem with other video sources is that the HDTV timings aren't what a monitor will usually get from a PC. This is particularly problematic in PAL-land, as 50Hz are unheard of on PC monitors, although I wouldn't be surprised if the NTSC "not-quite-60-Hz" caused havoc in the monitor circuitry. Of course, the reverse situation is just as bad. TVs expect TV timings on their HDMI inputs, they'll do overscan trimming, etc.