user: Question: What is the model number for the GPU and 320 MHz?
Columns: ['Model number', 'sSpec number', 'Frequency', 'GPU frequency', 'L2 cache', 'I/O bus', 'Memory', 'Voltage', 'Socket', 'Release date', 'Part number(s)', 'Release price ( USD )']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Atom E620', 'SLH56(B0)SLJ32(B1)', '600 MHz', '320 MHz', '512 KB', 'PCIe', '1 × DDR2-800', '0.8–1.175V', 'FC-BGA 676', 'September 14, 2010', 'CT80618005844AA', '$19']
SQL:

assistant: SELECT "Model number" FROM "Table" WHERE "GPU frequency" = '320 MHz';