HP TC4400 - Manual (Page 121)

5–38 Maintenance and Service Guide
Removal and Replacement Procedures
14. Rotate the display clockwise 90 degrees 1.
15. Remove the two Torx8 T8M2.0×20.0 screws 2 and the
two Phillips PM2.0×8.0 screws 3 that secure the display
assembly to the tablet PC.
Removing the Display Screws