Memory fun

[Jaime Bisceglia]

I am attempting to install extra memory in my DL380G6's.

For some reason, things seem to get screwy when I try to put three of these on a single channel:

http://h10010.www1.hp.com/wwpc/uk/en/sm/WF06c/A1-329290-64186-3924237-3924237-3916268-3957623.html

For reference here are the guidelines from the quickspecs:

http://h18000.www1.hp.com/products/quickspecs/13234_div/13234_div.HTML#Memory

My exact setup:

(6) of these: http://h10010.www1.hp.com/wwpc/uk/en/sm/WF06c/A1-329290-64186-3924237-3924237-3916268-3957623.html
(8) of these:
http://h10010.www1.hp.com/wwpc/uk/en/ho/WF06c/A1-329290-64186-3924237-3924237-3916281-3980705.html

For each side I put (3) 8G dimms in GDA, and (4) 4G dimms in BCEF.

Total memory recognized comes out to 48G instead of 80G.

If I remove the two 8G dimms from G on each side it will correctly post to 64G.

Thanks in advance,
Jaime

[Michael A. McKenney]

You have 8 x 4GB = 32GB currently. You want to add 6 x 8GB = 48GB for 80GB.

Remove all the 4GB. Install just the 6 x 8GB in proper slots, 3 per CPU. Do you get 48GB. Then start populating with 4GB. You always start with the largest first and work down.

[Terry Hutchings]

The second link you provided is for 16GB DIMMs, but you mention 4GB DIMMs. When installing the memory in this server you should install them alphabetically, instead of numerically. So the first 3 DIMMs for each CPU should be installed in A, B, and C not 1, 2, 3 which is how you currently have the 8GB DIMMs installed. Once you populate A, B, and C for each CPU you should add the other 4 DIMMs (4GB DIMMs, I guess) in slots D, E, F, and G.

[Jaime Bisceglia]

Sorry for the confusion, that last link should be for this 4Rank 4G dimm:

https://h10057.www1.hp.com/ecomcat/hpcatalog/specs/provisioner/99/500660-B21.htm

Just three 8G dimms on each side ABC works fine. The thing that makes things screwy is when 3 are on one channel. According to quickspecs there is a limit of 8 ranks per channel, so two of my 4Ranks+anything is a no go. But three of my 8G dimms should work.

Also: my 8G dimms are 1333MHz and the 4G are 1066Mhz, another reason why I keep the faster ones on the same channel.

The extra screwy thing is: when (3) 8's are on one channel, it doesn't recognize 16G on each side (32G total). I would expect it to not recognize that entire channel (24G per side 48 total). It's almost as if when there are (3) 8's in a channel, it then chooses to not recognize the other two channels.

[Michael A. McKenney]

I looked at boards from Supermicro and Tyan, they have similar memory gotchas. You really have to read the memory configuration rules and use the memory configurator on HP's site to upgrade their servers.

[Jaime Bisceglia]

The mem config tool does not provide a solution for 80G that can utilize my already owned 4G dimms which is of course the goal. I still figured I would be good since there is nothing in the quickspecs that state my config as specified at the top should not work.

[Terry Hutchings]

The memory config guidelines for the 380 G6 are as shown below (not all of them, but the ones that are pertinent to this situation):


DIMM slots that are white should be populated first
It is not required, but it is recommended to load the channels similarly if possible
You can only have up to eight (8) ranks installed per channel
You can only install two quad-rank DIMMs per channel
Populate DIMMs from heaviest load (quad-rank) to lightest load (single-rank) within a channel

Starting with the first bullet......I believe slots A, B, and C are the white ones. Are you populating these first? You will want to install the same type of memory in each of these 3 slots.

I included the bullets regarding quad rank dimms, since you apparently have 4GB QR DIMMs.