What's the directx of the model with code name RV770 PRO and a core bigger than 650.0 MHz?
CREATE TABLE "table1_19161046_1" (
  "model" text,
  "year" text,
  "code_name" text,
  "fab_nm" real,
  "bus_interface" text,
  "transistor_count_millions" real,
  "memory_max_mi_b" text,
  "core_m_hz" real,
  "memory_m_hz" text,
  "type" text,
  "bus_width_bit" real,
  "direct_x" text,
  "shader_model" text,
  "open_gl" text,
  "maximum_resolution" text,
  "ice_q4_cooling_system" text,
  "notes" text
);
SELECT "direct_x" FROM "table1_19161046_1" WHERE "code_name"='RV770 PRO' AND "core_m_hz">650.0;