CREATE TABLE table_27277284_27 (socket VARCHAR, frequency VARCHAR, model_number VARCHAR)

What kind of sockets does a 2100MHz Athlon X2 QL-64 use?
SELECT socket FROM table_27277284_27 WHERE frequency = "2100MHz" AND model_number = "Athlon X2 QL-64"
SELECT "socket" FROM "table_27277284_27" WHERE "2100MHz" = "frequency" AND "Athlon X2 QL-64" = "model_number"