That's not true I don't think. I know it can run on AGP 4x, but I think 2x was like 3.3v cards where now it's 1.5v, not entirely sure though but I think 2x is diff....not that it matters though since his is 4x it'll work
Yes you will see a massive performance increase from that TNT2 IMO
Yes the rest of your system will be somewhat limiting, but it will work none the less and the card will make a nice improvement overall
Processor: Intel Pentium 4/III/II/Celeron, AMD K6/Duron/Athlon/Athlon XP or compatible with AGP 2X (3.3V), 4X (1.5V), 8X (0.8v) or Universal AGP 3.0 bus configuration (2X/4X/8X).
Memory: 128MB or 256 MB