It reminded me of a problem I had a few years ago, about 10 minutes before my card died. So, I turned off, cleaned the card, all the fans and so on and turned back on - still there.
By a slight whim, I decided to try a VGA cable instead of my DVI and to my shock, it's fine.
However, I'd like to set my mind at rest that the problem is solved, not just "invisible" and instead my card will pack up tomorrow or the day after.
Could this have been a problem with the lead? I don't have a different DVI to try it with and I'd like to know if I should consider getting it back to the manufacturer (its a work PC) before something really bad happens.
did you use the dvi cable before of was it the first time you tried that cable?
there might be various reasons to the problem you faced.
1st your cable might be faulty.
2nd either the dvi plug of your card or your monitor might be faulty.
you can try swaping one thing at a time to give you a better idea about what the problem is.