Increase Bandwidth by 20%

Microsoft reserves 20% of your available bandwidth for their own purposes like
Windows Updates and interrogating your PC etc.

Click Start then Run and type

"gpedit.msc" without quotes.

This opens the Group Policy Editor.

Then go to: Local Computer Policy --> Computer Configuration --> Administrative Templates --> Network --> QOS Packet Scheduler

Then double click LimitReservableBandwidth.

It will say it is not configured, but the truth is under the 'Explain' tab i.e."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."

So the trick is to ENABLE reservable bandwidth, then set it to ZERO. This will allow the system to reserve nothing, rather than the default 20%.