I just bought a 50" LG Plasma screen (LG 50PV450) and planed on connecting it with my computer. Its a Win7 with a Radeon HD 4800 graphic card that has a HDMI, VGA and DVI output.
I connected the screen via HDMI with the computer, set it to 1080p and adjusted the refrate to 24hz. The picture looks awesome, though I have a very subtle but visible flicker in white areas (white not moving areas, e.g. on a website). The flicker is also more visible from the corner of my eyes if I dont look at it directly.
I tried a bunch of different stuff: changing the refresh rate to 23 and 60 hz (60 hz seems to flicker a bit more), changing the resolution, connecting them via VGA etc. nothing seems to work.
So I contacted LG and AMD, asking if they have a solution for the problem. LG referred to the manual saying that I need to have certain horizontal and vertical refresh rates to get rid of the flicker: