Uniwide Technologies XtremeServer 1322 User Manual page 27

NOTICE
How do we distinguish between single-rank and double-rank registered DDR DIMM Modules?
Both x4 and x8 registered DIMMs come in single-rank (single-sided) and double-rank (double-sided)
configurations. A single-rank x8 ECC DDR DIMM has 9 devices on the module and comes in two
different styles. A double-rank x4 ECC DDR DIMM has 36 devices in a stacked configuration on the module.
Both the double-rank x8 ECC DDR DIMM modules and single-rank x4 ECC DDR DIMM modules have
18 devices making them difficult to distinguish between (see Table).
Module Type
Single-rank (single-sided)
Double-rank (double-sided)
(Example 1) 184-Pin Single-Rank x8 ECC DDR SDRAM DIMM
Front
Back
(Example 2) 184-Pin Single-Rank x8 ECC DDR SDRAM DIMM
Front
Back
x4 DIMM
18
36 (stacked)
x8
Devive
Register PLL Register
x8
Devive
Register PLL Register
x8 DIMM
9
18
25