Acer Veriton X4620G Service Manual page 85

3. If a second memory module is available, install it in the DIMM2 slot by repeating step 1.
NOTE: Install memory rule as table shown below.
77
DIMM1 DIMM3
A
A
A B
B A
A A
A B
A B
B B
Remark:A and B show different size of memory, size:A>B
DIMM2 DIMM4
A
B
A
A
A B
B A
Chapter 3