Acer AR320 F1 Series User Manual page 61

Memory identification
Generally, there are some memory information printed on the label of
the DIMM module. Different vendors may have different formats but
the convention is usually like this:
Item Description
Density 1 GB, 2 GB, 4 GB, 8 GB.
This platform supports DIMM organized by 1 Gb or 2 Gb DRAM chips.
Rank 1R = Single Rank
2R = Dual Rank
4R = Quad Rank
Notes: If quad rank DIMM is used, a maximum of only two DIMMs per
channel can be supported. It is not recommend to mix DIMMs with
different ranks in one system.
Bit This platform supports x4 and x8. But x4 is only supported by Xeon
Organization X3400 series CPU.
Speed PC3 - 6400 => DDR3- 800
PC3 - 8500 => DDR3- 1066
PC3 - 10600 => DDR3- 1333
Density
Rank
Bit organization
Speed
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