CONFUSION ABOUT ADDING RAM to HP EliteDesk 705 G3 Microtower

[dondean]

I just had a "chat" with an HP support person and am confused by what they told me.
I recently purchased an HP EliteDesk 705 G3 Microtower PC and it came with 2 x 8 GB DIMM modules.

One in channel A and one in channel B.

I purchased two 16 GB DIMM modules that have the same specifications as the 8 GB DIMMs already in the PC.

I contacted HP using their "chat" to verify which DIMM sockets I should put the 16 GB DIMMs in and the chat person said that I can not mix 8 GB modules with 16 GB modules.

Here are 3 quotes from the "Hardware Reference Guide":

1. "you can populate the system board with up to 64 GB of memory"
2. "if Channel A is populated with two 1 GB DIMMs and Channel B is populated with one 2 GB DIMM, the system will operate in dual channel mode"
3. "For optimal speed, the channels should be balanced so that the largest amount of memory is spread between the two channels. If one channel will have more memory than the other, the larger amount should be assigned to Channel A.
   For example, if you are populating the sockets with one 2 GB DIMM, and three 1 GB DIMMs, Channel A should be populated with the 2 GB DIMM and one 1 GB DIMM, and Channel B should be populated with the other two 1 GB DIMMs. With this configuration, 4 GB will run as dual channel and 1 GB will run as single channel."
   -----------------------------------------------------

Since the four DIMM sockets will support 64 GB of RAM, this means it will work with 16 GB DIMMs.

Since the Reference Guide says you can mix 2 GB and 1 GB DIMMs, then

MY QUESTION is: "Why is there a problem using 8 GB and 16 GB DIMMs at the same time?"

I would put one 8 GB and one 16 GB in each channel, so the channels would be balanced with 24 GB each.

Before I could ask the support person this question, the chat was disconnected and later I received an email saying that my ticket number had been closed.

This is frustrating, as I feel like I was cut off and was not able to get a good answer.

Any advice would be appreciated. Thanks 
Don

[CF4]

Hi

Hope this helps.

http://h10032.www1.hp.com/ctg/Manual/c05263117   Page 23

There are four DIMM sockets on the system board, with two sockets per channel.
The sockets are labeled DIMM1, DIMM2, DIMM3, and DIMM4.
Sockets DIMM1 and DIMM2 operate in memory channel B.
Sockets DIMM3 and DIMM4 operate in memory channel A.
The system will automatically operate in single channel mode,
dual channel mode, or flex  mode, depending on how the DIMMs are installed.

NB:- Single channel and unbalanced dual channel memory configurations will result in inferior graphics performance.

The system will operate in a higher-performing dual channel mode if the total memory capacity of the DIMMs in Channel A is equal to the total memory capacity of the DIMMs in Channel B.

[dondean]

Thanks for the quick response CF4.

The link you listed gives a "404 Not Found error"

Most of what you stated is in the "Hardware Reference Guide".

I did not get the answer or information I was looking for. Let me restate my questions.

>> The chat support person said you can not mix 8 GB DiMMs and 16 GB DIMMs. Is this true?
(The Reference Guide indicates that you can mix different size DIMM modules and run in dual channel mode if the channels are balanced.)

>> If I put one 8 GB and one 16 GB in each channel, so the channels would be balanced with 24 GB each, would this work OK and run in "dual channel mode" with no problem?

Don

[CF4]

Hi

>> The chat support person said you can not mix 8 GB DiMMs and 16 GB DIMMs. Is this true?

I don't know what conversation you had, but I will accept that you did have a conversation and are reporting it accurately.

https://support.hp.com/gb-en/product/HP-EliteDesk-705-G3-Microtower-PC/10669598

http://h10032.www1.hp.com/ctg/Manual/c05263117

The system will operate in a higher-performing dual channel mode if the total memory capacity of the DIMMs in Channel A is equal to the total memory capacity of the DIMMs in Channel B.

[dondean]

Thanks again for your quick response CF4.

Thanks for the new links.

Unfortunately this information does not answer my question (I will try again):

>> Will it work or not work to have one 8 GB DIMM and one 16 GB DiMM in each channel so each would be balanced with 24 GB each? (The Reference Guide says you can mix 2 GB and 1 GB DIMMs)

If you don't know the answer, then please just say so, rather than give me more links to follow (unless the links will answer my question.)

This is a "copy and paste"  of the text of the discussion I had with the chat support person (I don't know how to attach a file from my PC to this discussion.)

-------------------------------------------------------------

3/28/2018
1/1
12:41 PM Connecting...
12:41 PM Connected. A support representative will be with you shortly.
12:42 PM Support session established with Shainitha.
12:42 PM Shainitha: Thank you for choosing HP Active Chat Support. My name is Shainitha . How are you doing today?
12:43 PM Don Pfortmiller: Just fine thank you.
12:47 PM Shainitha: I would need couple of moments while i check on this issue
12:47 PM Don Pfortmiller: OK
12:48 PM Don Pfortmiller: If this will take awhile, could you email me the answer?
12:51 PM Shainitha: Could you please confirm how many memory modules were shipped with the unit?
12:51 PM Don Pfortmiller: Two 8 GB modules
12:52 PM Don Pfortmiller: One was in channel A black and one was in channel B black
12:53 PM Shainitha: Could you please confirm if you have purchased one memory module of 16 GB or 2 memory module of 8 GB?
12:53 PM Don Pfortmiller: Two modules of 16 GB each so a total of 32 GB
1:02 PM Shainitha: iam sorry for the late response Don
1:02 PM Don Pfortmiller: OK
1:03 PM Shainitha: You could either use 16 GB and 16 GB combination or 8GB and GB combination it is not possible to use 8GB and 16 GB
memory module together
1:03 PM Shainitha: because the combination should be 32 GB or 16 GB in total
1:05 PM Don Pfortmiller: I ;thought this computer would take up to 64 GB
1:07 PM Don Pfortmiller: This is a quote from the product specifications:
1:07 PM Don Pfortmiller: The memory sockets on the system board can be populated with up to four industry-standard DIMMs. These
memory sockets are populated with at least one preinstalled DIMM. To achieve the maximum memory
support, you can populate the system board with up to 64 GB of memory confi gured in a high-performing
dual channel mode.
1:07 PM Shainitha: It would take 64 GB ,but you should use all 16 GB module
1:08 PM Shainitha: you cannot have 8GB module and 16 GB module combination
1:08 PM Shainitha: Either 8 GB in all the slots or 16 GB module in all the slots
1:09 PM Don Pfortmiller: What if I put the 16 GB modules in one channel and the 8 GB modules in the other channel, would that work in a dual
mode
1:16 PM Connection lost. Attempting reconnection...
1:15 PM Shainitha: Unfortunately that is not possible Don
1:16 PM Connecting...
1:16 PM Connected. A support representative will be with you shortly.
1:16 PM Support session established with Shainitha.
1:18 PM Connection lost. Attempting reconnection...
1:18 PM Connecting...
1:18 PM Connected. A support representative will be with you shortly.
1:18 PM Support session established with Shainitha.
1:20 PM Connection lost. Attempting reconnection...
1:20 PM Connecting...
1:20 PM Connected. A support representative will be with you shortly.
1:20 PM Support session established with Shainitha.
1:21 PM Printing chat transcript

[krzemien]

I understand your feelings very well when it comes to getting credible and concise response from Support.

Still! I think having a mixture of 8GB and 16GB RAM modules should just work - and why not?

It's probably much more important for them to sit in correct memory banks so dual-channel mode is recognised correctly.

So, with this in mind: why don't you just give it a go and try?

And report back?

[dondean]

Thanks krzemien.

Yes, it does seem to be a bit difficult in getting a concise answer to my question.

I'm not a hardware expert and I'm concerned that if I put the RAM in as I want to, and if this is not compatible with the PC that I could do some kind of damage. Either to the RAM or to the mother board.

I don't want to have to replace either, I'm on a tight budget.

It seems to me also that it should work, but I'm fearful of taking the chance.

Don

[krzemien · Accepted solution]

Understood.

The only damage you can inflict would be by inserting modules incorrectly / physically damaging slots or modules themselves etc. So if you do not have an experience or are afraid of doing so, either get somebody to help you with this task - or get the whole PC to some service guys nearby who will do it for you.

If that helps: this is the link to ASUS mobo (I just chose it randomly) that uses the same chipset as your PC (AMD B350 FCH, correct?):

http://dlcdnet.asus.com/pub/ASUS/mb/SocketAM4/PRIME_B350-PLUS/E13723_PRIME_B350-PLUS_UM_V3_WEB_20171...

On page 1-12 you can read:

• You may install varying memory sizes in Channel A and Channel B. The system

maps the total size of the lower-sized channel for the dual-channel configuration. Any

excess memory from the higher-sized channel is then mapped for single-channel

operation.

• Always install DIMMs with the same CAS latency. For optimal compatibility, we

recommend that you install memory modules of the same version or date code (D/C)

from the same vendor. Check with the retailer to get the correct memory modules.

[dondean]

Thanks a bunch krzemien.

I don't have a problem with installing the RAM myself, except for the concern I previously mentioned.

I was trying to figure out how to find information on the system board, and the link you provided looks like the board that I have.

I could not find any information in the "Hardware Reference Guide" that mentioned the motherboard that was used in the PC.

• How did you determine this?

If I can verify that this is the board that I have, or if not, get the information on my board, and see what it says about varying memory sizes, then I will be a "happy camper".

Don

[dondean]

Hey krzemien, you were right.

The hardware document that I downloaded from HP did not list the chipset information, but I found a datasheet that did and it is the AMD B350 FCH.

So I feel confident that the 8GB and the 16GB DIMMs should work together OK.

Thanks.