What is the TDP (w) of the chipset with a codename sb850?
CREATE TABLE "a_link_express" (
  "model" text,
  "codename" text,
  "released" text,
  "fab_nm" real,
  "sata" text,
  "usb_2_0_1_1" text,
  "usb_3_0" text,
  "parallel_ata_1" text,
  "raid" real,
  "gb_ethernet_mac" text,
  "package" text,
  "tdp_w" real
);
SELECT COUNT("tdp_w") FROM "a_link_express" WHERE "codename"='sb850';