So, the first site I thought to check was AmIRight, a place where people can submit misheard lyrics. Their page on Jay Z, suggests that it's G's, not cheese.
I then decided to see if I could find it on Jay Z's official site, since this was second hand. Unfortunately, neither the Def Jam, nor the Roc-A-Fella Jay Z pages contain lyrics for the song. Jay Z Online (apparently run by Rab Basement Network) though has lyrics, as do all of these web sites.
Looks like it's G's and not cheese . . . which really does make a lot more sense as g is slang for a grand or a thousand . . .