Buying a Cable Modem

I have time warner cable and they are going to start charging customers a fee for renting their modems. So I would like to plan on buying a modem. 

I don't know much about modems other than how to put them together. 

Are they certain ones that I can only buy using time warner? 

Also I don't what would be the best for my speed (25mbps)

Thanks in advance

 

needs to support the speed. also, i belive time warner uses dhcp for ip allocation, so any off the shelf one should work. call time warner and they can help you set it up. (as you will most likely need to input credentials for authentication)

ok thanks.