Gee, I was reading this BBS to see if I could find a problem similar to mine, and there you go.
I had EXACTLY the same problem.
Now I reinstalled win2k - the prob is gone.
I was using sp1, dx8beta, IE 5.5.
My specs:Gigabyte 7-IX, 128Mb, K7 700, G400 DH 32Mb, Sblive, Diamond Supraexpress 56k external. Latest drivers and bios for everything.
Now I wonder what the problem is, it was really anoying having to reboot every time I wanted to reconnect to the internet...