I am having a problem with my internet connection. I have two different broadbands at my home Sky and BT, I am on a desktop PC and used to switch between these quite happily for different purposes. About 2 weeks ago I was testing another Sky router (which works) to try and set it up elsewhere in the house, since then I can connect to my normal Sky router but it it takes about 30 minutes before it decides to connect to the internet once and then it goes off and on frequently. I know the problem is not the router i'm using as I have 2 other computers set up on it which never disconnect, also the broadband light is always on so its definitely not that. I have thoroughly searched and tried all the solutions i've found, most being for laptops due to wireless, however I do not have a wireless adapter. I have tried uninstalling my driver, updating my driver, using OpenDNS, letting the settings be set automatically and setting them manually. I am at a total loss now, the only thing windows (7) tells me is that my "dns server is not responding". Can anyone give me any help

It sounds to me like you have both routers connected to the same network, both offering DHCP service and both trying to be the default gateway. Disconnect the second router and see if that makes any difference. If so, you'll need to isolate the second router on its own physical network if you intend to keep on using it.