Troubleshooting guide

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Cisco UCS B200 M3 Blade Server Installation and Service Note
OL-26624-01
Memory and Performance
Memory Performance
When considering the memory configuration of your blade server, there are several things you need to
consider. For example:
• When mixing DIMMs of different densities, the highest density DIMM goes in slot 0 then in
descending density (ex: A0: UCS-MR-1X162RY-A , A1: UCS-MR-1X082RY-A, A2:
UCS-MR-1X041RY-A)
• Your selected CPU(s) can have some affect on performance.
• DIMMs can be run in a 1DPC, a 2DPC, or a 3DPC configuration. 1 DPC and 2DPC can provide the
maximum rated speed that the CPU and DIMMs are rated for. 3DPC causes the DIMMs to run at a
slower speed.
Memory Mirroring and RAS
The Intel E5-2600 CPUs within the blade server support memory mirroring only when an even number
of Channels are populated with DIMMs. If one or three channels are populated with DIMMs, memory
mirroring is automatically disabled. Furthermore, if memory mirroring is used, DRAM size is reduced
by 50 percent for reasons of reliability.
4 (Blue slots) A0, B0, C0, D0 E0, F0, G0, H0
5 A0, B0, C0, D0
A1
E0, F0, G0, H0
E1
6 A0, B0, C0, D0
A1, B1
E0, F0, G0, H0
E1, F1
7 A0, B0, C0, D0
A1, B1, C1
E0, F0, G0, H0
E1, F1, G1
8 (Blue and black slots) A0, B0, C0, D0
A1, B1, C1, D1
E0, F0, G0, H0
E1, F1, G1, H1
9 A0, B0, C0, D0
A1, B1, C1, D1
A2
E0, F0, G0, H0
E1, F1, G1, H1
E2
10 A0, B0, C0, D0
A1, B1, C1, D1
A2, B2
E0, F0, G0, H0
E1, F1, G1, H1
E2, F2
11 A0, B0, C0, D0
A1, B1, C1, D1
A2, B2, C2
E0, F0, G0, H0
E1, F1, G1, H1
E2, F2, G2
12 (Blue, black and beige slots) A0, B0, C0, D0
A1, B1, C1, D1
A2, B2, C2, D2
E0, F0, G0, H0
E1, F1, G1, H1
E2, F2, G2, H2
Table 2 Preferred DIMM Population Order
DIMMs per CPU CPU 1 installed slots CPU 2 installed slots