that's somewhat common with radeon cards and some catalyst drivers. does your card have dual dvi ports? if so, try moving the monitor to the other port. are you using a VGA-to-DVI adapter? if so, try to find another adapter.
you can also try installing the latest drivers and then change the DVI settings. open CCC, select Digital Panel/Attributes, and set 'Reduce DVI frequency' and/or 'Alternate DVI operational mode'.
I recently bought an ACER AL2223WD monitor and after I installed it on my pc I started to get random black screens. It gets much worse depending on how complicated the graphics for the program I am running on it. Google Earth makes it go nuts as does Solidworks (AutoCad).
It worked okay on my old Phillips 150B 15" LCD monitor
I already tried the monitor out on a HP workstation and it worked beautifully so I know that the monitor is not the issue.
I updated every driver, made sure the PC recognized the monitor (this took a bit of doing as it resisted doing so), and updated all the Catalyst software. It's set to the recommended refresh rate and settings (60Hz, 1,650 X 1,050 resolution, high color 32 bit).
Windows XP SP3
OCZ GameXtreme 700W powersupply
Abit AS8V m/b
Intel P4 650 3.4Ghz w/Zalman 7600 series fan
2Gb Kingston DDR400 Ram
Visiontek Radeon x1550 256mb ram AGP
Soundblaster Audigy ZS
Acer AL2223WD 22" Widescreen LCD monitor
Western Digital 60gb 7200rpm HD
One more thing..old info. Why can't the Abit AS8V boot up with an ATI 9800 All-in-wonder Pro 128 video card?