My solution to slow speedtests (was 3.5Mb now 9.5Mb)
Thought i'd share this...
My router DownStream Connection Speed was showing about 11054 kbps but the speed test sites eg Namesco BroadbandMax ADSL Broadband Bandwidth speedtest | Test your ADSL Broadband connection speed were showing about 3.5-4Mbps connection.
my network card was set with a receive buffer size of 8Kbps (Control Panel -> Network Connections -> [Your SKY Connection] -> Properties -> Configure -> Advanced)
maybe it was causing false readings or maybe it is actually slowing down data between the router and the computer... but I set mine to 64kbs and my "speed" reported by speedtest sites increased from a 3-4Mbs average to a 9.5Mbs average.
hope this helps someone