This tweak is designed for broadband users:

1.Log on as “Administrator”.

2. Run – gpedit.msc

3. Expand the “Local Computer Policy” branch

4. Then expand the “Administrative Templates” branch

5. Expand the “Network” branch

6. Highlight the “QoS Packet Scheduler” in left pane.

7. In the right window pane double-click the “Limit Reservable Bandwidth” setting

8. On the settings tab check the “Enabled” item

9. Change “Bandwidth limit %” to read 0

10. Then go to your Network connections Start=>Connect to=>Show All Connections and
right-click on your connection. Then under the General or the Networking tab,
(where it lists your protocols) make sure QoS packet scheduler is enabled.

It may take effect immediately on some systems. To be sure, just re-boot.