VT6122 VT6130 don't work on vista x64 with over 4GB RAM

[tantan]

Hi

I have Gigabit LAN VT6122 on vista x64 with 8GByte RAM.
but VT6122 don't work.

1GByte RAM : work
2GByte RAM : work
3GByte RAM : work
4GByte RAM : don't work
5GByte RAM : don't work
6GByte RAM : don't work
7GByte RAM : don't work
8GByte RAM : don't work

Is this VIA Velocity driver's problem?

thanks