user: Question: What is the v-core for a stepping of G1 and frequency of 1900MHz?
Columns: ['Model Number', 'Stepping', 'Frequency', 'L2 Cache', 'Multi 1', 'V Core', 'Socket', 'Release Date', 'Part Number(s)']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Athlon X2 BE-2300', 'G1', '1900MHz', '2 × 512 kB', '9.5×', '1.25 V', 'Socket AM2', 'June 5, 2007', 'ADH2300IAA5DD']
SQL:

assistant: SELECT "V Core" FROM "Table" WHERE "Stepping" = 'G1' AND "Frequency" = '1900MHz';