Lenovo ThinkPad T400 Service And Troubleshooting Manual page 61

c. If your model has a touch pad or a fingerprint reader, detach the
connector of the palm rest cable by pulling the tab with your fingers.
Now the palm rest has been removed.
6. If the two SO-DIMMs are already installed in the memory slots, remove
an SO-DIMM to make room for the new one by pressing out on the
latches on both edges of the socket at the same time. Be sure to save it
for future use.
7. Find the notch on the contact edge of the SO-DIMM.
Attention: To avoid damaging the SO-DIMM, do not touch its contact
edge.
Chapter 5. Upgrading and replacing devices
51