I personally own a Mitsubishi 20780SB-BK 22" and an ATi AIW R9700 Pro AIW. It's a great setup! However, two things...
First, my friend and I seem to be noticing a trend. He has a 22" NEC FE1250 and an AIW R8500. When running 1600x1200@85Hz@32bit, he AND I both experience severe flickering on the screen. There are faint, but very noticable, horizontal lines that scroll up and down. VERY annoying! We also both experience this thing where sometimes the screen flickers/jolts like there is a power surge/spike. The screen fades to black and back to normal again. This happens all within a very short period of time...we're talking you have to have your eyes open to see it. If you blink, you could miss it. It doesn't happen that often, but when you're typing or reading, you see it a lot.
Second, when running high refresh rates at high resolutions (ie: 1600x1200@85hz or 2048x1536@85Hz :yes my AIW 9700 Pro supports this @32bit colour

the text becomes blurry or unreadable. However, this isn't the situation when I hook up my nVIDIA cards.
Is there a known issue with ATi cards? This is pretty bizzare. My friend and I don't own the same monitor, but we experience the same issues. His previous card was a Matrox G450 Millennium and he had no issues *at* all. Flawless performance all the time.
I currently run 1600x1200@75Hz, of which I experience ZERO problems and text is sharp enough to cut glass. However, at 2048x1536, text looks only good at 60Hz, but my eyes would die in a heartbeat if I had to keep it at that refresh rate. I planned to run 2048x1536@85Hz, which is feasable with my setup, however, it seems as if our ATi cards are the limiting factor. Anyone have a Matrox Parhelia for sale?
Sorry for kind of going OT with this, but since I own this monitor and you may have an ATi card, it's worth looking into. Maybe I should start a thread dedicated for this issue/flaw?
Please PM me if you have any ideas/details to fix my solution or would like to give input.
Thanks,
jamesbond007