ARGH!  I have a Dimension 8250.  When it was connected to my cable modem, the internet was speedy.  Then I got greedy.  I connected it to a Belkin 2.4g-802.11g wireless router.  For a couple of days it continued to work fine and the laptop in the house works all the time.  Then the Dimension internet connection got painfully slow every time I was on it.  I decided to increase the RAM from 256 to 512, thinking that would speed up the system.  It worked great - for a day.  Then it was back to 20 minutes or so to connect to a site.  In frustration, yesterday I disconnected everything, reconnected to the cable modem to make sure that wasn't the problem.  Speedy connection.  Then I reconnected to the router and again, it worked great.  I was so proud!  8-10 hours later, we're back to turtle-like slowness.  I'm going crazy trying to figure it out.  Any suggestions?