Low signal strength = modem slow or disconnecting

I'm using WOW cable and lately (possibly due to cold weather) my modem has been disconnecting and or not being able to connect to the cable company. We have three rooms with TVs along with a cabal modem. We have the cable coming from outside split two ways. One to the modem and another which goes to another splitter for the TVs. The problem is that because that the initial signal coming into the house has gotten worse (again probably since it's winter) and because the signal is so split up, the modem isn't receiving enough.

Back in the summer the modem was receiving somewhere between 0 to -2dBmV. Now it is receiving somewhere between -18 to -20dBmV. If I disconnect the TV's it goes back up to around -6 to -8dBmV.

What I want to do is get a signal amplifier. Does anyone know of a good one that will work with both the Internet and the television?

Front page article, gives amp info and splitter info. Look that over.

http://www.overclockers.com/articles1154/