Follow this simple steps>>>
1]Click on start, select run and type "gpedit.msc".
LOCAL COMPUTER POLICY
-->QOS PACKET SCHEDULER
-->LIMIT RESERVABLE BANDWIDTH.
3]Double click on "limit reservable bandwidth" and then select "Enabled" and edit the bandwidth to O.
Its a nice trick...!! try it and get internet speed 20% more..!!
Note:For some versions of windows like windows home basic versions don't have gpedit.msc command,in that case just ignore this trick...(it is not work)