Follow the steps to speedup 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.
Speedup Vista download:
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.