Acer Altos R910 - Manual (Page 50)

3 System upgrade 40
Removing the center brace
You will need to remove the center brace to remove and install an
optional processor core VRM.
To remove the center brace
1 Observe the ESD precautions and pre-installation instructions
described on page 33.
2 Slide the chassis at each side of the chassis to the unlock position
(A).
3 Lift the center brace from the chassis (B).