3 Cable Modems

[G-Stress]

Hey guys, am in the process of testing something. I have 3 cable modems, 1 all valid/legit from my ISP and 2 older one's I've had from awhile ago. I decided to hook them all up and of course 2 of them pulled a 10.?.?.? ip for registration purposes. I did notice that if I copy my legit ip info and assign it to the adapter in use on another machine with one of the other modems connected only changing the last number in the IP itself that I was able to get online with very slow speeds upon download. Not really noticeable when browsing only when downloading. It starts out quick but then slows down quickly as well. After sometime it does loose it's connection to the net and needs to be either power cycled (to re-download the config file) or change the ip.

Was curious if anyone else has had any experience with this and been successful using 2 or more cable modems and getting the rated speeds on both modems. This site has some pretty good info as well as kit's to do what I'm attempting to do (http://www.tcniso.net/) but I'd like to do it without the purchase of these kits/tools.