If you install the QoS Packet Scheduler (Psched.sys), you can limit the combined bandwidth reservations of all programs running on your Windows 2000 system by setting the NonBestEffortLimit value name, a REG_DWORD data type, to a percentage, between 0 and 100, of the total connection bandwidth. The default value is 20 percent.
The system wide setting is located at HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\Psched. You can make adapter specific settings by using NonBestEffortLimit at HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Psched\Parameters\Adapters\Adapter-GUID.
NOTE: Adapter specific settings take precedence.