DDR4 Only Socket Level Population Requirements
DDR4 Socket Level Minimum Population Requirements
•
There should be at least one DDR4 DIMM per socket.
•
If only one DIMM is populated in a channel, then populate it in the slot furthest away from CPU.
•
Always populate DIMMs with a higher electrical loading in DIMM0 followed by DIMM1.
DDR4 Only Memory Populations with Possible Mixes
DDR4 RDIMM
DIMM0/DIMM1
Config. Set A
Within
DDR0
x8, None, x8, x8
IMC
DDR1
None or same as
DIMM
DDR0
Popula-
tion
DDR2
None or same as
DDR1 (excludes
DIMM 1 in 5DIMM
configurations)
DDR4 Only Memory Populations with Possible Mixes
3DS LRDIMM or 3DS RDIMM
DIMM0/DIMM1 Config. Set A
Within IMC
DDR0
DIMM Popu-
DDR1
lation
DDR2
DDR4 Only Memory Populations with Possible Mixes
LRDIMMs
Within IMC
DDR0
DIMM Popu-
DDR1
lation
DDR2
Purley DDR4 Only 2SPC Memory Configuration with x8 DIMMs
Total # of
DIMMs
DIMM Population
1 x8 DIMM
within an IMC
(Note: Uniformly
populate with x8
2 x8 DIMMs
DRAMs DIMMs)
3 x8 DIMMs
4 x8 DIMMs
5 x8 DIMMs
6 x8 DIMMs
DIMM Population
1 pair of
within an IMC
DIMMs
(Note: Non-equal
in rank pair of x8
2 pairs of
DIMMs)
DIMMs
3 pairs of
DIMMs
2 pairs+1
(5DIMMs)
DIMM0/DIMM1
DIMM0/DIMM1 Con-
Config. Set B
fig. Set C
x4, None, x4, x4
x8, x4, or x4, x8
None or same as
None or same as
DDR0
DDR0
None or same as
None or same as
DDR1 (excludes
DDR1 (excludes DIMM
DIMM 1 in 5DIMM
1 in 5DIMM configura-
configurations)
tions)
x4, None, x4, x4
None or same as DDR0
Cannot mix 3DS LRDIMM and RDIMM
None or same as DDR1
DIMM0/DIMM1
x4, None, x4, x4
None or same as DDR0
Note: Requirements
*Match DIMM types installed across DDR
None or same as DDR1
channels within an IMC
*Always populate iMC0 first
DDR Channel
Must be installed on iMC0 DDR Channel 0
DDR0: Populate with 1 DIMM
DDR1: Populate identically as DDR0
DDR0: Populate with 1 DIMM
DDR1: Populate identically as DDR0
DDR2: Populate identically as DDR1
DDR0: Populate with 2 DIMMs
DDR1: Populate identically as DDR0
DDR Channel 0, 1, 2: DIMM0 is populated with identi-
cal DIMMs,
DDR Channel 0, 1: DIMM1 is populated with identical
DIMMs
Populate 2 DIMMs per DDR channel
DDR0: Populate with 1 DIMM
DDR1: Populate the second DIMM (for best perfor-
mance)
DDR0: Populate with 1 pair of non-equal rank DIMMs
DDR1: Populate identically as DDR0
DDR0: Populate with 1 pair of non-equal rank DIMMs
DDR1: Populate identically as DDR0
DDR2: Populate identically as DDR1
DDR0: Populate with 1 pair of non-equal rank DIMMs
DDR1: Populate with identical DIMMs as DDR0
DDR2: DIMM0 is populated with identical DIMM as
DDR1
35
Chapter 2: Installation
Possible Mixes
DIMM0/DIMM1
Single Rank, None
Single Rank, Single Rank
Dual Rank, Single Rank,
Dual Rank, None
Dual Rank, Dual Rank,
Single Rank, Single Rank
Possible Mixes
DIMM0/DIMM1
Quad Rank, None
Quad Rank, Quad Rank
Possible Mixes
DIMM0/DIMM1
Quad Rank, None
Quad Rank, Quad Rank
Number
Virtual
of Ranks
Lock Step
1
N/A
>1
SVLS
1
N/A
>1
SVLS
1
N/A
>1
SVLS
x
SVLS
>1
SVLS
x
SVLS
1
N/A
>1
SVLS
1
N/A
>1
SVLS
x
SVLS
>1
SVLS