There actually aren't anywhere close to 2000 tapes in Frasier's cabinet. Each small section contains 12 tapes. There are 6 sections in each columns and 11 columns are completely full. The 12th column contains 4 sections and Frasier puts the "2000th" tape in the first slot in the 5th section. This means that in total, there are only 841 tapes in the cabinet.