IBM THINKPAD S05L-1270-01 - Manual (Page 504)

Step Size (quantity) Torque
4 M2.5 x 4 mm (1) 3 kgcm
Note: Make sure you use the correct screw and tighten the
screw to the torque specified. Do not use the screw that you
removed, use a new screw.
492 IBM Mobile Systems HMM