CREATE TABLE table_18823880_10 (l2_cache VARCHAR, release_date VARCHAR, part_number_s_ VARCHAR)

When by80607002529af is the part number and september 2009 is the release date what is the l2 cache?
SELECT l2_cache FROM table_18823880_10 WHERE release_date = "September 2009" AND part_number_s_ = "BY80607002529AF"
SELECT "l2_cache" FROM "table_18823880_10" WHERE "BY80607002529AF" = "part_number_s_" AND "September 2009" = "release_date"