I have an (allegedly) 15mbps cable connection from Comcast with a pretty standard setup - cable modem plugged in to Netgear router, which serves one PC via an ethernet cable and several laptops via wireless.
The problem is that, on the desktop only (running Vista), DNS frequently fails. It will work fine for half an hour or so, and then I'll start getting DNS lookup errors, even on sites I've been actively browsing - but not all sites at once, some still work. If I run a command shell as an admin and run ipconfig /flushdns then everything starts working fine again for another period of time. But it is extremely annoying.
All the settings, on both the PC and the router, have "Automatically acquire DNS Server address from ISP" set. And it seems to work fine on all the other computers on the network.
Very puzzled. Any help would be appreciated, I just don't know networking that well.