I have two virtually identical Athlon 64 systems (same motherboards, same nVidia GeForce Optima 5700 LE video cards, same 1 gb of memory, and HD-3000 HDTV tuner cards). The main differences are that one system uses FC4 and the latest nVidia driver and the other uses FC2 and an earlier nVidia driver. I use both systems to schedule, record, and view HDTV programs (using crontab, pchdtvr, and mplayer on the FC4 system and crontab, dtvstream, and xine on the FC2 system). The problem has to do with the output from the nVidia video cards. Both systems use the same xorg.conf files (using the same HDTV 1080i modelines.) The FC2 system outputs interlaced 1920x1080 (1080i) which looks great on an HDTV monitor. Unfortunately, the FC4 system using the same card and modelines on the same HDTV monitor produces a display that seems to be trying to reduce interlace flicker (which produces an inferior display). I can't find the source of the difference between the two systems. I guess it has to be either the OS difference or the difference in the version of the nVidia driver. I've looked through the driver info to find an option to change on the FC4 system but in vain. Both systems produce identical 960x540 noninterlaced displays (540p). Any ideas on how to fix the FC4 system? I would like to move the FC2 system to FC4 but not if the display is inferior. Is there something FC4 is doing to reduce the interlace flicker? BTW, using a GeForce 5200 card on the FC4 system has the same exact problem (so the brand new 5700 card in the FC4 system is unlikely to be defective). Rick B.
