How to increase the Browsing and Downloading speed in Vista?
With windows Vista you have noticed the slow internet speed. The web
browsing and downloading speed is very slow as compare to previous
versions of windows. You can open the same sites in windows XP and
server 2003 with the normal speed.
Follow the given steps to increase the Vista browsing speed:
First go to Advance
tab in Internet Explorer and turn off the TLS (Transport
Layer Security)
encryption option. Here to fix problem with some secure pages turn on
the SSL 2.0 (Secure
Sockets Layer) feature and click Ok button to close it.

Follow the major fix for this problem:
In
windows Vista, the TCP autotuning feature is enabled by
default. Some web servers do not respond properly to
this feature, so it appears that some sites open with
very slow speed.
To use this feature, you will need to be logged into
your computer with administrative rights.
First click on Start button and type CMD in Run
option then press Enter.
At Command Prompt, type the following command and press
enter.
netsh interface tcp set global autotuninglevel= disabled
This command will disable the TCP
autotuning feature. Now close
the command Prompt and restart your computer after any
changes to go into effect.
You can easily restore these setting by typing
the following command at Command Prompt.
netsh interface tcp set global autotuninglevel= normal
Now close the command Prompt and again restart your
computer after any changes to go into effect.