once again, thanks guys! i'll try that, in the meantime, i switched off hardware acceleration for my video card, it solved the problem. incidentally, this issue was brought to my attention by the mandrake installer, when i decided red hat could go and suck a fat man. interestingly, mandrake offered me much more versatility at install time than red hat did. Unfortunately it looks like hardware acceleration being disabled means i can't have transparent xterms and so on, and also hardware acceleration works in windows which sucks a lot.
As for sound card and modem, i am planning to buy a swannsmart serial modem and a terratec 128i sound card in the hope that they will magically solve my problems. one can only hope. In the meantime i am now onto getting bloody mplayer installed. I installed libdecss and libdvdread fine, and then i installed mplayer (0.60) without a hitch, but not having much luck playing a DVD. tried with Xine too, it tells me it won't play encrypted DVDs. the DVD in question is a normal copy of Grease from Australia. well, i am not really asking for help with this one, since i don't think anybody's reading this anyway...