9 out of 10 video card manufactures dupe ppl into buying 256 meg cards when all that does for you is put you into a lower quality card with butt slow ram. Check the specs sometime, 256 meg video card using 3.8-4.4 NS ram 128 meg cards running strong @ 3.0-3.6 The PCB is even known to be 4-6 layer instead of 8, No game on the market can use 128 meg no reason to move to a 256.
Sometimes you can get high end ram on a 256 meg card but the usual is low dollar slow memory.