What I can say about that is that you should definitely get the cpu/mobo upgrade. The V3 isn't that bad a video card. What's really limiting your PC is the K6-2 processor. - really really weak FPU. I believe that when you get the new cpu/mobo and use that same video card, performance would be way better. Had this same problem with my Savage4 (16MB). I first used it with my K6-2+ 533. It wouldn't even play WMP visualizations smoothly. Then I used it with my Celeron 500. It ran really really well!!! Even in the benchmarks I ran, using it with the Celeron scored double as compared to when using it with the K6-2.
Core 2 Duo E8500, ASUS P5Q SE, 4GB DC PC2-6400, 2 x 1TB SATA-II, GeForce GTX260, Creative SB Audigy 2 ZS
Core 2 Duo E7500, ASUS P5QL PRO, 4GB DC PC2-6400, 2 x 500GB SATA-II, GeForce 8800GT, Creative SB Audigy 2 Value
P4 650, ASUS P5GD1 PRO, 4GB DC PC3200, 2 x 300GB SATA, GeForce 9500GT
Pentium D 925, ASUS P5RD1-VM, 2GB PC3200, 2 x 160GB, GeForce GT220