Deconf DIMMs

[Subentu]

I have a Rx7620 server running HP-UX 11.23i

I had 16GB of RAM installed and while doing a power cycle, a cell board failed. I replaced the cell board and installed the DIMMs from the faulty cell board to the new cell board.

Now server sows only 14GB of RAM.

The output of the command "echo "selclass qualifier memory;info;wait;infolog" | cstm" is shown below:

Basic Memory Description

Module Type: MEMORY
Page Size: 4096 Bytes
Total Physical Memory: 16384 MB
Total Configured Memory: 14336 MB
Total Deconfigured Memory: 2048 MB

Memory Board Inventory

DIMM Location Size(MB) State Serial Num Part Num
-------------------- -------- ------- ---------------- ------------------
Cab 0 Cell 0 DIMM 0A 1024 Config A56E05276344 A6098-60101
Cab 0 Cell 0 DIMM 0B 1024 Config A56E05276341 A6098-60101
Cab 0 Cell 0 DIMM 1A 1024 Deconf A56E05276288 A6098-60101
Cab 0 Cell 0 DIMM 1B 1024 Deconf A56E05274291 A6098-60101
Cab 0 Cell 0 DIMM 2A 1024 Config PRY08011NT A6098-60101
Cab 0 Cell 0 DIMM 2B 1024 Config PRY0750127 A6098-60101
Cab 0 Cell 0 DIMM 3A 1024 Config PRY08011XT A6098-60101
Cab 0 Cell 0 DIMM 3B 1024 Config PRY08011LN A6098-60101

Cab 0 Cell 0 Total: 8192 (MB)

===========================================================================

DIMM Location Size(MB) State Serial Num Part Num
-------------------- -------- ------- ---------------- ------------------
Cab 0 Cell 1 DIMM 0A 1024 Config A56E05274292 A6098-60101
Cab 0 Cell 1 DIMM 0B 1024 Config A56E05274278 A6098-60101
Cab 0 Cell 1 DIMM 1A 1024 Config A56E05274283 A6098-60101
Cab 0 Cell 1 DIMM 1B 1024 Config A56E05318669 A6098-60101
Cab 0 Cell 1 DIMM 2A 1024 Config PRY08011Z3 A6098-60101
Cab 0 Cell 1 DIMM 2B 1024 Config PRY08054P2 A6098-60101
Cab 0 Cell 1 DIMM 3A 1024 Config PRY08011M6 A6098-60101
Cab 0 Cell 1 DIMM 3B 1024 Config PRY0750183 A6098-60101

Cab 0 Cell 1 Total: 8192 (MB)

===========================================================================

Memory Error Log Summary

The memory error log is empty.

[AnthonySN]

some rules for memory from another post in itrc from VK2COT.

Here are the memory loading rules for RX7640:

a) Memory must be installed in pairs
(two DIMMs of equal size);

b) Minimum memory is 2 GB per cell (RX7640
can have up to two cells);

c) Larger DIMMs must be loaded first across
a cell, followed by progressively smaller
DIMMs;

d) On each cell board, memory pairs must be
installed in the following order:

(0A, 0B), (1A, 1B), (2A, 2B), (3A, 3B),
(4A, 4B), (5A, 5B), (6A, 6B), (7A, 7B)

e) DIMM mixing other than recommended
configurations is supported as long as
memory loading rules are followed.

f) Load memory equally across the available
cell boards;

g) For best performance, a cell should
be configured with a multiple of eight
DIMMs or four pairs (although the server
will work with an odd number of pairs).
It takes eight DIMMs to populate both
memory buses. If only one memory bus is
populated, the cell board will deliver half
the peak memory bandwidth.

[Raj D. · Accepted solution]

Subentu,

Seems in Cell#0 , 2 DIMM not seated properly.
IA & 1B. You have to do it again, have power it off, open cellboard, re-open the dimm connect back in the slot firmly.

Cab 0 Cell 0 DIMM 1A 1024 Deconf A56E05276288 A6098-60101
Cab 0 Cell 0 DIMM 1B 1024 Deconf A56E05274291 A6098-60101




Before you can boot the os , you need to interrupt in EFI and use the command at EFI prompt:

info sys
info memory

When you will see all the 16GB memory, that is all memory are correcly loaded , and then only boot it into multiuser mode by rebooting it again.


Hth,
Raj.

[Subentu]

"Load memory equally across the available
cell boards"

Does having 8GB in one cell and 6GB in the other harm the server ? Or this rule is for best performance only ?