nic very slow, need advice about driver!

Hello people,
I was doing some benchmarks today and saw that our PDC has a very slow throughput. It was supposed to be about 10MB per second. It was getting at best 1.2MB per second!!
This is terrible! I tried updating the driver…no good. I tried uninstalling it and reinstalling the new driver….no good. I saw this problem before on a workstation and after about one hour of trying the above things….I formatted and reinstalled the OS. I really don’t want to do this on the NT server…it has a lot of services running on it.
To reinstall it would take a whole saturday!! Does anyone have any ideas on what I could do to get the nic speeds closer to 10MB per second??

thank you,
Oskar