Hmmm... this is a weird one.
Well, if the fan on your card has, indeed, stopped then it might be overheating, though I would expect that it wouldn't do it so quickly that the monitor is blue on startup. The card itself may have just died.
The other thing I think this could be attributed to is your OS itself (i'm assuming you're using Windows of some sort). It's possible you got yourself a virus or Windows just hiccuped or something.
See if you can take your hard drive and put it in another machine. Test to make sure that you can boot into your OS and play around just fine. If you can, then you know it's not the hard drive or any OS problems. Otherwise, you'll have to take a closer look at your graphics card. However I'd also take that graphics card and stick it in a working machine to test that too. Assuming both your hard drive and graphics card work fine in other machines (when used separately AND together), then you know it's something entirely different, in which case I'd start looking at your RAM.
Try some of this stuff and post your results.