HP Deskpro EN Supplementary Manual page 37

3-12 Upgrading the Computer
CAUTION:
Your DIMM sockets have gold metal contacts. When
upgrading your memory, it is important to use DIMMs with gold
metal contacts (not tin-lead) to prevent corrosion and/or oxidation
resulting from having incompatible metals in contact with each
other.
CAUTION:
Static electricity can damage the electronic com-
ponents of the computer or optional boards. Before beginning
these procedures, ensure that you are discharged of static
electricity by briefly touching a grounded metal object. Refer to the
Safety, Care & Regulatory Information guide for more information.
CAUTION:
When handling a memory module, be careful not to
touch any of the contacts. Doing so may damage the module.
To insert or remove a memory module:
1. If you have locked the Smart Cover Lock, use Computer
Setup to unlock it.
2. Turn off the computer and any external devices.
3. Disconnect the power cord from the power outlet, and
disconnect any external devices.
4. Remove the computer cover.