Lockstep mode, Lockstep mode single processor configuration – Acer AR360 F1 User Manual
Page 70
3 System upgrades
54
Note: 1. Place DIMMs in “X” location. DIMM population must
correspond to the above tables.
2. DIMM modules support 1 GB, 2 GB and 4 GB DIMMs.
3. DIMM modules support 8 GB and 16 GB DIMMs (support
depends on availability).
4. Do not mix UDIMMs with RDIMMs.
5. 3-DIMM per channel configuration is only available for
single/dual rank RDIMM.
Lockstep mode
•
In Lockstep Channel Mode, each memory access is a 128-bit data access
that spans Channel 1 and Channel 2. This is done to support SDDC for
DRAM devices with 8-bit wide data ports. The same address is used on
both channels such that an address error on any channel is detectable by
bad ECC. Lockstep Channel mode is the only RAS mode that supports x8
SDDC.
•
Channel 3 has no function and can't be populated in this mode.
•
Follow the population rules described in independent mode.
•
Lockstep mode needs the channel 1 & channel 2 with identical DIMM.
DIMM slot populations within a channel do not have to be identical but
the same DIMM slot location across channel 1 and channel 2 must be the
same. DIMM1A and DIMM2A should be the same type, size and
manufacturer. DIMM1B and DIMM2B memory should be the same type,
size and manufacturer. DIMM1C and DIMM2C memory should be the
same type, size and manufacturer.
•
Same rule is applied to the CPU2.
Lockstep mode single processor configuration:
E
X
X
X
X
X
X
NA
NA
NA
X
X
X
X
NA
NA
NA
F
X
X
X
X
X
X
NA
NA
NA
X
X
X
X
X
X
NA
NA
NA
Channel 1
DIMM slots
Channel 2
DIMM slots
Channel 3
DIMM slots
Notes
Configuration
1C
1B
1A
2C
2B
2A
3C
3B
3A
A
X
X
NA
NA
NA
B
X
X
X
X
NA
NA
NA
CPU1
CPU2