How to solve huge problem?

[Smarty]

Good morning All,

I have a huge problem. I hope you can help me or give me a trace about the problem. I got an internet 768 kb/s. It has the transfer between 80 and 85 kb/s but unluckily its between 40 and 45 kb/s.
Anybody knows what it can be? Like windows.netcard.the supplier.modem ?

Cause I have already format c:/, I have tested with other netcard of my other computer and it got the same problem.
We have tested the modem with other one. Not equal and it was without success. And uninstalled the program that could interrupt the connection but it wasn’t the cause of the problem.

Does anyone else know? How to solve this problem?