Computer ip on DHCP?

So I left a P2P program open and exheeded the college network's daily upload limit.  Now I'm off the net for awhile. I'm guessing if I can change my computer's ip number, then it'll recognize my PC as another and I'm back in business. How do I do it? I've tried:

ipconfig /release
ipconfig /renew

at the command prompt, but no dice. Anything else I need to try?

Also, network settings may or may not be locked out from me... but where do I go to see if it is or isn't?

>>8
No. In fact, that's one reason why it's possible to change the MAC address. MAC was not meant for security purposes, just unique identification. MAC address collisions do occur more often than you'd think.

The problem is that the first three bytes of a MAC address specifies the card manufacturer (what a waste). That leaves three bytes to uniquely identify the card. If you're running a large network you'll sometimes end up with cards that have the same MAC on the same segment, particularly if you bought all your cards from the same manufacturer.