Few of you know that Microsoft reserved for the operating system Windows XP, o internet band (bandwidth) of 20%, for certain system services. Windows Update, System Error Report, etc. Gen services.
Using a small System setting, in Group Policy, we can allocate less Internet band for these services.
First of all, we must open xp Group Policy Editor.
Start -> Run -> GPEDIT.MSC -> OK or enter.

In Group Policy, we go to the left menu at Local Computer Policy -> Computer Configuration -> Administrative Templates -> Network -> Qos packet scheduler. Selected QOS Packet Scheduler, and the panel on the right side we are looking for: Limit Reservable Bandwidth.
Double-click to open limit reserve bandwidth, then tick the box next “Enable“, to allow ourselves to set as far as the Internet band we want to reserve it for system services.

By default, this limit is set to 20%, but we can allocate 0% to benefit from all Download speed.
Limit Reservable Bandwidth – Explain :
Determines the percentage of connection bandwidth that the system can reserve. This value limits the combined bandwidth reservations of all programs running on the system. By default, the Packet Scheduler limits the system to 20 percent of the bandwidth of a connection, but you can use this setting to override the default. If you enable this setting, you can use the “Bandwidth limit” box to adjust the amount of bandwidth the system can reserve. If you disable this setting or do not configure it, the system uses the default value of 20 percent of the connection.