Simpler Navigation for Servers and Operating Systems
Completed: a much simpler Servers and Operating Systems section of the Community. We combined many of the older boards, so you won't have to click through so many levels to get at the information you need. Check the consolidated boards here as many sub-forums are now single boards.
Operating System - Tru64 Unix
cancel
Showing results for 
Search instead for 
Did you mean: 

ES45 1B Memory Question

SOLVED
Go to solution
MrEdu
Occasional Advisor

ES45 1B Memory Question

First let me start off that I am new to the alpha world and was given 4 - 1GB DIMMs to upgrade our ES45 1B system. Now sets 0,1,2,3 already have 4 - 256MB DIMMs. What is the recommended configuration to get the maximum amount of memory?
5 REPLIES
Steven Schweda
Honored Contributor

Re: ES45 1B Memory Question

MrEdu
Occasional Advisor

Re: ES45 1B Memory Question

Sorry I did go through the docs and I am just looking to confirm.

Current Setup
MMB0 - 4 x 256 = 1GB
MMB1 - 4 x 256 = 1GB
MMB2 - 4 x 256 = 1GB
MMB3 - 4 x 256 = 1GB

Now I am looking to replace a set of 4 x 256 with 4 x 1GB DIMMs. Which Bank is the best and supported to pull out and replace to get the max memory.

From what I read would be to pull out MMB1 and replace with the 4 - 1GB DIMMs and then leave MMB3 Empty. This would give me a tolal of 6GB. Is that correct or can I just take out MMB3 and swap the 256 with the 1GB for a total of 7GB.

These are fantastic forums!

Thanks!
From MrEdu
Rob Leadbeater
Honored Contributor

Re: ES45 1B Memory Question

Hi,

The usual best practice is to put the largest DIMMs in the lowest bank, so put your 4 new DIMMs in bank 0. The configuration rules are normally printed on the inside of the system cover.

Note however that whatever you do, you'll change the memory interleaving from 4-way, which may have an effect on the memory speed...

Hope this helps,

Regards,

Rob
Hein van den Heuvel
Honored Contributor
Solution

Re: ES45 1B Memory Question

From the links Steven provided you can find the owners guide which in chapter 4.9 extensively documents the process:
http://h18002.www1.hp.com/alphaserver/download/ek-es450-ug-b01.pdf

Nothing to add really: tables, pictures, rules.

Sounds like you have the 4 bank, 16 dimm configuration right?

With the 32 dimm config you should fill 0 and 4 and 1 and 5 with 256 DIMSM to get those to interleave and stick the 4-1GB DIMMs in 2.

With 16 slots, ther eis nothing much you can do. Since there are just 4-gb dimms you will not have interleaving for that, nor for 1 of the 4-256 sets, and 2-way for the other 2 4-256.

People smarter than use might be able to use, or avoid, the 2 way interleave, for example by using a GH section which will land on a predictable set of physical memory, but if it's that critical, then somehow getting an other set of 4-1GB would seem the better way to go.

If the system is currently almost happy with 4GB, and really just an additional 2GB will make it very happy, then I would consider to populate 0 and 1 with 4-256, stick the 4-1G in 2, and leave 3 empty for a total of 6GB. Run with that for a week taking some performance indications (collect, 'time' for a job'.
Now add 4-256 back for 7GB, run for an other week and compare jobs.

So while I would be inclined to also stick the 4-1GB in 0, to do the above #2 might be handier. It matters little.

Do be sure to issue >>> SHOW MEMORY for every config. Both now, and after adding.

Enjoy!
Hein.
MrEdu
Occasional Advisor

Re: ES45 1B Memory Question

First let me say thank you to everyone who replied.

Here is what we ended up doing.

We removed the last bank of 4 x 256MB DIMMs and replaced with 4 x 1GB DIMMS.

The additional memory has helped and as of yet have noticed no real negatives. If something comes up I will update.

Once again thanks to everyone!