I use XP with 5.9, version 7.1 I use Vista x86(desktop) and x64(laptop).
www.speedguide.net
Run TCPOptimizer to make sure your connection is wide open. Reboot.
You didn't mention if you are trying to do this wirelessly, but make sure you can get a 300Mps connection.
If you can try pinging the AIM servers, it just might be your geographic location or your neighborhood.