By default, Windows XP Pro reserves 20% of the bandwidth of Internet connections in case of network congestion by using a tool called “Packet Scheduler.”
Attention, this is not the case with Windows XP Home, for which no bandwidth reservation is made. This trick is unnecessary for Windows XP Home.
You can override this value by changing the parameter specifying the percentage of reserved bandwidth.
To do this, open the packet scheduler:
Start / Run / gpedit.msc
(Gpedit.msc exists only in the Windows XP Professional)
In the left menu, select:
Local Computer Policy / Computer Configuration / Administrative Templates / Network / QoS Packet Scheduler
Then in the right pane, click “Limit reservable bandwidth”.
A configuration window opens. The “Bandwidth Limit” to specify the amount of bandwidth that the system can reserve. If you disable this setting or do not configure it, the default value (20%) is used.
Thus it is necessary to click on “On” and then enter the value 0.
Click Apply, then OK, close all windows and restart the computer configuration to reflect the change.
• What for?
In practice, the QoS does not affect navigation or the download, but about how Windows manages access to networks of different flow rates. The only time it seems useful to disable it is in conflict with the network drivers, whose symptom is a blockage of the transmission of audio MSN Messenger (the gossips say that only Microsoft can make its own technologies not compatible with each other).