Right we all know vista is horrible and I used to get lag every 60s seconds because the way vista wireless networks work. It scans every 60 seconds causing a lag spike. This ruins cod4 and alot of games and peeves me right off. How ever I just came across a fix.

Before you start press windows key and r then run cmd

In cmd type ping google.co.uk or google.com if your in usa and put /t and the end
i.e. ping google.co.uk /t

if every 50-60 seconds you notice time fo from 40-60ms to about 1000ms then you are getting lag spikes. The fix is rather simple.

Download WLAN optimizer from [ Register or Signin to view external links. ]

Extract to a folder, I called mine WLAN

Run the program

It opens in a small window, go to the settings tab and tick all the boxes.



Now open cmd and type ping [ Register or Signin to view external links. ] /t again and after 50-60 seconds you shouldn't see time go abnormally high.

Hope this helps as it did for me . comment if it works.