ATI 200 tv tuner card

Hi I have had this card up and fully functional at one point with great results in the past esp w/ capturing video from the TV portion and w/ recording from my VCR
however now Im experiencing poor recordings being jittery/jerky I cant as of yet isolate the problem there were a few things thay may be culprit of this (1) is the CMC fouled up and required reinstall
(2)the old MMC was installed as well as CMC
(3) the auto update from SP2 to SP3 So If someone could please assist with this issue Thanks!
System NFO :HP 1.01gb CPU-
512mb ram nothing special or great
As I said I once was able to record media w/ clean results on this exact system before