Cable Modem O/C

I have a cable modem in my house and i am wondering what would overclocking it do?

If you know the model, check out DD-WRT, Tomato and others. They do offer overclocking on boxes that allow it.

Speaking purely on overclocking it, if it was being limited by the processor, it would allow more throughput. If you have hundreds or thousands of connections (torrenting, for example), it might help out.

Its Motorola. And how would it affect gaming and surfing the web? And describe what more throughput is... Im still a bit new to most terms that involve networking...

Throughput, how much data it can transfer in a given time.

If you were doing nothing but browsing the web or gaming, probably not.