Internet disconnects and reconnects frequently

OS: Windows Vista 6

My computer is wired directly to a modem and router and my ISP is AT&T DSL.

Modem: Motorola MSTATEA
Router: Belkin Surf F7D2301 v1

I still have Local Area Connection but not Internet Connection.

My internet disconnects every 2-3 minutes for about 20 seconds and this lasts for 1-2 hours. Then it happens again later on (I'd say 4 times a day).

If you need more information I'd be happy to tell you.
 
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