What was found
IAH - DURING INITIAL APPROACH THE CREW REPORTED SMOKE IN THE COCKPIT, THE CREW PERFORMED AN EMERGENCY DESCENT, AND THE AIRCRAFT LANDED AT IAH WITHOUT INCIDENT. MAINTENANCE INSPECTED THE AIRCRAFT, AND REMOVED AND REPLACED THE FIRST OFFICERS MFD, OPERATIONALLY CHECKED WITHOUT DEFECT, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.