Cannot display page

When connected (dial up) I can view web pages for 3 to 4 minutes before Cannot display page, server not found message comes up.

Connection is still present and I can successfully ping or tracert.

Disconnecting and redialing gives me another three or four minutes.

Downloading files keeps going

Adaware and Spybot show nothing and I have scanned with Mcafee and Norton with no problem.

Running XP SP2 and have disabled anti virus , fitrwall and everything else I can think of

Thought it was an IE6 problem but the same thing happens using Firefox

Did once see a message flashing through the screen about stack overflow 0 – thought this was not an XP thing!

Any ideas?

Garth