Best I Ever Had So Far Gone Drake

buzz so big i could probably sell a blank disc

He is saying that the clammour prior to his album coming out is so immense that his CD could be blank and people would still purchase it.
Drake is simply saying that everyone is looking forward to his album so much that he could sell a blank disc and everyone would rush out and buy it before anyone caught on... that's pretty good
he is saying that sex, love and pain is such a huge issue to talk/sing about i could probabaly label a blank disc with that topic(s) and actually sell it.