Dell OptiPlex XE3 Small Form Factor Service Manual page 63

9 Install the:
a M.2 PCIe SSD
b Memory module
c Processor
d Heat sink
e Heat sink fan
f Heat sink duct
g Hard drive and optical drive module
h HDD assembly
i Front bezel
j Side cover
10 Follow the procedure in After working inside your computer.
Disassembly and reassembly 63