I guess my previous reply didn't post, or was deleted for some reason. Anyway, in it, I made sure to point out that Windows XP is not ALWAYS reserving 20% of your download bandwidth for updates, so disabling this won't really "give" you more bandwidth. You'd only see a difference when windows updates is actively downloading updates while you're downloading a lot of stuff. Besides, the size of downloads aren't so intrusive that you'd really notice a difference over a long period of time, so you might as well leave well enough alone. If you really want to see more bandwidth, you should tweak settings like Max MTU, or RWIN, or TTL settings--optimal settings will be specific to your router/gateway/modem and also to your ISP, and these make a huge difference as the default windows values are optimized for dial-up modem users, not broadband users. For example, with the default windows values, my download speeds were only about 250 kilobits/sec max, and optimized for my ISP, they are over 3000 kilobits/sec. There are programs to do this--just do a google search. But in disabling the QoS or bandwidth reserve, you won't really notice a difference in general browsing or downloading, so it's probably best to not interfere with the defaults of automatic updates (if you're using automatic updates).