z620 upgrade RAM: can I add 2x4GB to work with 4x2GB?

[TsDin]

Hello all, 

I've already checked Memory Configurations and Optimization chart, however I"m still not sure if the following memory configuration will run smoothly: 

I"m running a single Intel Xeon E5-1620, 

I have: 4x of SK Hynix HMT325U7EFR8C-PB T0 AB 2GB DDR3 PC3-12800E ECC   installed. 

I want to add 2x of SK Hynix 4GB 1Rx8 PC3L-12800E-11-13-D1 HMT451U7BFR8A-PB TO AB

That should make it 16GB in total, however, in the specs I can't find such a configuration. 
Does that mean it's not legitimate ? 

Thanks a million in advance. 

I"m a bit stuck with that... 

[BambiBoomZ · Accepted solution]

TSDin,

There is nothing that prohibits a 4X 2GB + 2X 4GB memory configuration in a z620.  

>1.  Use only memory having the HP part number on it. 

2. However, do not mix PC3 with PC3L- the "L" meaning the RAM will run at a lower voltage when possible. Use only PC3.

3. The memory will work better if both channels are complete, that is: 4X + 4X.  Place the larger capacity modules in the 1st channel (black slots).

4. The best performance appears to occur when the modules are all the same capacity- I don't know why, perhaps something to do with the progressive memory saturation.  I had a z420 (E5-1620) that had 4X4GB + 4X 2GB and the memory benchmarks were noticeably better with 4X 4GB only.  I've noticed this effect too in Passmark baselines.

5.  It's good policy to plan ahead so as to allow an increase in capacity to 32GB.  That may not be necessary,  but I think of 16GB today as the minimum for a workstation and 32GB as the sweet spot. Every computer I've ever owned but one needed more memory over time, including the 1993 IBM 486 DX2/50 MHz when adding 1MB cost $180 (=$180,000 per GB!).  I had another z420 (E5-1660 v2) with 32GB and I eventually discovered that large rendering setups required 37+ GB. The exception to having to add is the current z620 which has had 64GB from the beginning.  Consider adding  4X 4GB to the current 4X 2GB (=24GB) so that by replacing the 4X 2GB, a future 4X 4GB could be added for 32GB.

BambiBoomZ 

HP z620_2 (2017) (R7) > Xeon E5-1680 v2 (8-core@ 4.3GHz) / z420 Liquid Cooling / 64GB DDR3-1866 ECC Reg / GTX 1070 Ti 8GB / HP Z Turbo Drive M.2 256GB AHCI + Samsung 970 EVO M.2 NVMe 500GB + HGST 7K6000 4TB / > HP OEM Windows 7 Prof.’l 64-bit > 2X Dell Ultrasharp U2715H (2560 X 1440)

[TsDin]

Hi, BambiBoomZ  

Thanks a lot for your quick and truly helpful advice. 

As I understood, my proposed configuration of 2x4GB + 4x2GB should work, however that would be much better to have 4x4GB installed instead of only two.  

I see the point that same-size memory will perform better, but I don't want to loose my 4x2GB. I wish to install them along with 4GBs. But I'm a bit concerned with what you've said about benchmarks being better when not having different sizes installed.  Does it mean 4x4GB alone will perform better than 4x4GB +4x2GB? 

Another issue I am facing is to actually buy the suitable memory. Since I'm located outside US, I'm a bit limited with the options. I've been trying to find something on Amazon and ebay, but that's tricky as I need to get a very specific module.
Do you know if there's a practise to sell used parts here in the community? 

Once again - apprecaite your help a lot! 

[BambiBoomZ]

TsDin,

Yes, 2x4GB + 4x2GB  will work.  My experience and whem looking at benchmarks  has indicated that having a uniform size of module produces a better benchmark.  However, day to day, I don't think it would be noticeable, that is, the system would not seem to have excessive lag.

If you'd like to keep the 4X2GB, then consider adding 4X 4GB in the first channel to the original 4X 2GB for a total of 24GB.

There is no provision to sell parts in the commuunity.  If you're able to purchase from an EU Ebahhh, it should be quite easy to find suitable memory.  There and on US Ebay as well, meny of the vendors are in Hong Kong anyway and should ship anywhere. For example on ebay.de:

https://www.ebay.de/itm/RAM-8GB-2X4GB-PC3-12800E-SAMSUNG-M391B5273DH0-CK0-Unbuffered-ECC-DDR3-HP-1-5...

That example shows the HP part number sticker for 4GB of PC3-12800E : P/N 662609-571.

Verpackung und Versand

Artikelstandort: default, Hong Kong

Versand nach: Weltweit

Ausgeschlossen: Algerien, Angola, Benin, Botsuana, Burkina Faso, Burundi, Kongo, Demokratische Republik, Dschibuti, Elfenbeinküste (Côte d'Ivoire), Eritrea, Gabun, Gambia, Ghana, Guinea, Guinea-Bissau, Kamerun, Kap Verde, Kenia, Komoren, Kongo, Republik, Lesotho, Liberia, Libyen, Madagaskar, Malawi, Mali, Marokko, Mauretanien, Mauritius, Mayotte, Mosambik, Namibia, Niger, Nigeria, Réunion, Ruanda, St. Helena, Sambia, Senegal, Seychellen, Sierra Leone, Somalia, Swasiland, Tansania, Togo, Tschad, Tunesien, Uganda, Westsahara, Zentralafrikanische Republik, Simbabwe, Ägypten, Äquatorialguinea, Äthiopien, Afghanistan, Anguilla, Antigua und Barbuda, Aruba, Bahamas, Barbados, Belize, Britische Jungferninseln, Kaiman-Inseln, Dominica, Dominikanische Republik, El Salvador, Grenada, Guadeloupe, Guatemala, Haiti, Honduras, Jamaika, Martinique, Montserrat, Niederländische Antillen, Nicaragua, Panama, St. Kitts und Nevis, St. Lucia, St. Vincent und die Grenadinen, Trinidad und Tobago, Turks- und Caicosinseln

This is not a specific recommendation for that particular vendor, only an example.  I should mention that one must be careful with HK vendors, especially when something is notated as "new other", as I think the meaning there for that term appeears to be a bit more "generous".

By the way, you can also use PC3-12800R which is ECC registered in a z620.  in the current z620, I'm using PC3-14900R  (DDR3-1866 ECC registered. As the ECC registered RAM is universal in servers, there are huge piles of it and the price is noticeably lower.  Of course, server use may mean one to three years of 100% load for 24/day, That way, if a 2nd CPU is ever added to the system, all the 12800E RAM does not need to be replaced.  The performance using ECC unbufffered is slightly better.

What else was I going to say about memory? -I forgot!

BambiBoomZ

[TsDin]

Thanks, BambiBoomZ, 

I will give a closer look to ebay.

Just one thing - is that OK to have RAMs from different brands, i.e. I have SK HYNIX and the one you showed as an example is Samsung.  

Also I'm wondering if I can check that an HP part number 662609-571  is correct for Z620. 
So far I was able to find only an HP part number, which is A2Z48AA. 

In other words, what's the parametr / code I must check carefully to ensure that it will match? 

as for combining ECC registered and ECC Unbuffered, here's what HP says: 
"Unbuffered and Registered DIMMs cannot be mixed in a system." 
I don't know whether that's true or not, but I'm not sure I want to check it myself  😉 

Thanks for all your help - you've made my life much easier! 

[BambiBoomZ]

TsDin,

With workstation memory, I like to have the modules be as similar as possible, including the maker.  I think that's not going to mean it won;t work- as long as it has an HP part number, but all the modules of the same size - 8GB, 4GB or 2GB should be a set of identical modules.  This is because different brands might have different timings- although with HP probably not. In the current z620_2, there are 8X 8GB that are all identical Samsung.  When I had z420_1 the original memory supplied new was 4X 2GB Samsung, so when 4X 4GB was added, those were HP marked Samsung 4GB. z420_2 (E5-1660 v2) arrived new with 4X 4GB and I added 4X 4GB of identical RAM and z420_3 was used, having 1X 4GB so 3X that same 4GB was added. If the subject system has Hynix, then do searches for HP Hynix PC3-12800E, only as an example:

https://www.ebay.com/itm/SK-HYNIX-16GB-4X-4GB-DDR3-1600-PC3-12800E-ECC-SERVER-RAM-MEMORY-HP-662609-5...

> and note that note that the HP part number is the same 662609-571 for the Hynix 5GB as for the Samsung.  I think the timing is the same also- 11-12-E3.

As mentioned in the first reply, ECC unbuffered (E) and ECC registered (R) can not be mixed.  Nor can ECC and non-ECC nor regular power and low power.

It is because of all the small variables that my policy is to match the original RAM in every way possible, with only the module size being different. Out of dozens or RAM purchases, I only ever had one module that didn't work/ It was correct one, but defective, presenting "training errors" on booting.

Very pleased to help- there's a lot of fussy stuff to know about those little sticks!

BambiBoomZ

[TsDin]

Hey BambiBoomZ, 

hope you're doing fine, 

I just wanted to let you know that today I've received 4x4GB HP662609-571 Hynix RAMs and it works! 

I'm now running on 24GB and it gives a significant boost 😉 

Once again - many thanks for your help. 

You're the one who made it possible for me! 

All the best, 

Denis