human
Considering the provided database schema and associated query, produce SQL code to retrieve the answer to the query. 
###Database Schema: Model, Code name, CPU support, FSB / HT (MHz), Southbridge
###Question: What is the Southbridge when the CPU support was athlon, athlonxp, duron( socketa ), alpha21264?
gpt
SELECT Southbridge FROM table WHERE CPU support = athlon, athlonxp, duron( socketa ), alpha21264