CREATE TABLE table_46638 ("Model Number" TEXT, "Frequency" TEXT, "L2-Cache" TEXT, "Front Side Bus" TEXT, "Multiplier" TEXT, "Voltage" TEXT, "Socket" TEXT)

What is the Voltage for Model Number c3 866?
SELECT "Voltage" FROM table_46638 WHERE "Model Number" = 'c3 866'
SELECT "Voltage" FROM "table_46638" WHERE "Model Number" = 'c3 866'