CREATE TABLE table_63538 ("Model number" TEXT, "sSpec number" TEXT, "Frequency" TEXT, "Turbo" TEXT, "Cores" FLOAT, "L2 cache" TEXT, "L3 cache" TEXT, "I/O bus" TEXT, "Mult." TEXT, "Memory" TEXT, "Voltage" TEXT, "Socket" TEXT, "Release date" TEXT, "Part number ( s ) " TEXT, "Release price  (  USD  ) " TEXT)

What is the release date of the 6 mb L3 cache with the part number by80607005259aabx80607i7740qm?
SELECT "Release date" FROM table_63538 WHERE "L3 cache" = '6 mb' AND "Part number(s)" = 'by80607005259aabx80607i7740qm'
SELECT "Release date" FROM "table_63538" WHERE "L3 cache" = '6 mb' AND "Part number(s)" = 'by80607005259aabx80607i7740qm'