ATI AIW x1900 wierdness

Have ATI AIW X1900. Has been working perfect for over a year. My sys: AMD 4600+, 2G mem, Asus A8N-SLI Deluxe. Last night I turn the machine on and my View Sonic 22" wide screen monitor shows the XP Pro splash screen, then says 'No Signal' and goes dark. (I had it running fine earlier in the day, and I did not make any changes, add software or anything in the last 2-3 weeks) I realize after a couple re-boots with the same results that it probably has somehow enabled the second monitor and switched mine off. I hooked up my plasma TV to the component out from the breakout box, and I'm right. After much ado, I can't get it back to normal. It seems the digital output side of the card quit working, as I disconnected the digital monitor cable, and hooked up a VGA cable to the appropriate output and input of my card and Monitor, and it works fine! As a mater of fact, I notice no difference in the quality of the picture on my monitor, so I'm inclined to say 'problem solved', but I'm concerned this problem may be an indicator that the card is starting to go bad. Any thoughts? Thanks!