My roommate and I recently started mining bitcoins through slush's pool, neither of us have any clue really what we are doing but are really eager to learn.

I'm running a core2duo and nvidia quadro 600 and run at about 16.4Mh/s
My roommate however is running an Intel 6 core and integrated amd and nvidia quadro 600.

Now the issue is he pulls the exact same Mh/s rate that I do, but there is no way my computing power should be able to keep up with his,
my pc is atleast 5 years older.

Any help would greatly be appreciated also I will continue to search for an answer to this question on the forums!