Ram question for Z840

[Dean512]

Hello, I am trying to upgrade my ram and somehow I am now only able to put ram on the right side (CPU 1) only and achieve getting 64gb of ram but I want to balance it between both processors. I went into system settings and do in fact see it is recognizing both processors. I tried to look in bios if there was an option to activate cpus ram slots but have had no luck. I followed the slot order on the case and still no luck. 

I double checked msconfig and in advanced I made sure 2 processors are selected. 

is it possible that mismatched ram 16gb and 8gb can only work for one cpu and not the other? 

is there a way to activate ram slots so they recognize somehow that I am not seeing? 

thanks for help!

[DGroves]

For details on the supported memory configurations on the HP Z840 Workstation, refer to the System Technical Specifications - System Board section 

DIMMs should be equally distributed across all four memory channels for optimal performance.

Each processor supports up to 4 channels of DDR4 memory. To realize full performance at least 1 DIMM must be inserted into each channel.

The CPUs determine the speed at which the memory is clocked. For example, if a 1600MHz capable CPU is used in the system, the maximum speed the memory will run at is 1600MHz regardless of the specified speed of the memory.

You cannot intermix LR DIMMs with Registered DIMMs. The system will not work.

Maximum memory capacities assume Windows 64-bit operating systems or Linux

http://www8.hp.com/h20195/v2/GetPDF.aspx/c04400043.pdf

http://h10032.www1.hp.com/ctg/Manual/c04823811

[Dean512]

Hey thanks for the reply, So I tried to go back to just using 4 sticks of the original ram (one stick per set of 4 of the memory banks - original setup)  and it still will not recognize on CPU0. 

CPU0 simply is just not booting up to any ram. Is there a function to wake up the Ram slots or something? Its almost as if it needs to be activated again somehow. I did try to reset the cmos..and it does say my bios is updated but not sure if it is just saying it is updated. 

How can I get the motherboard to reset back to the original ram? Thanks for help! 

[DGroves · Accepted solution]

the newer cpu's like the ones in your z840 have the memory controller on the cpu as such sometimes cleaning the cpu pads and reseating the cpu will restore missing memory channels

keep in mind that the memory socket could also be damaged, carefully inspect the mem socket

[Dean512]

It’s hosed l, what should of taken 20 seconds has taken hours of wasted time. I will just use 64gb of ram on one cpu and the other will just ride solo making the machine basic at best. Oh well sometimes you try and increase performance but end up stuck out with a polished turd in the end. Next machine I will be wiser just to buy factory. I’ll want a new rig in a couple years anyways so no sense wasting more time on this as long as it works. 

Thanks for replies and assistance.

[DGroves]

what is the "numa" setting in the bios?    Select Non-Uniform Memory Access (NUMA)

also if 16gb modules don't register on one cpu, try installing 8gb sticks for both sockets as a test using 4 sticks

i had one z820 system that failed reading 8gb on several sockets but would read 4gb and 16gb sticks as long as the 16gb sticks were single banked/sided modules

also, try swapping cpu's in their sockets to see if the issue is with the cpu itself

[Dean512]

The bios has no ram selection, which I tried to explore...and I do not have the qualifications to remove a cpu or to swap cpus, I am a consumer, I went to great lengths just to learn the basics of how things work, a total waste of time. 

IMO HP should make a product designed for a consumer, not a computer pro. 

Troubleshooting only goes so far with a consumer, then you just cut your losses and say "this is why" people do not buy PC computers. 

Its a wash, and hopefully nobody tries to buy a HP product and upgrade ram (which is shown to be a practical and simple way to enhance a computer) in reality it is a complete nightmare and can cost you a lot of money. 

Onward to waiting until I upgrade:) Hopefully if you stick a third party stick of ram into a HP machine it will not go kuput entirely and ruin peoples investment. But as like any other corporation, they don't care what looks like a simple solution, money is the overall goal, and I am sure cost cutting in design/engineering. 

I will say this is why Mac works, people complain about their price/compadibility but you wont get screwed when trying to perform what looks like a logical and alluring task to a product. 

complete garbage. This is what a consumer thinks. 

[DGroves]

blaming HP for your lack of knowledge or skill level while human nature, is counterproductive and not really HP's fault. 

while i do understand your frustration on this issue please try to understand that blaming a maker of a product you are unable to get working is not going to address the issue

you not HP decided to make changes to a working system  and it's you not HP that has to read the numerous doc files such as the system maintenance guide and the ram placement guide and other informational files that HP offers online and decide if you understand them well enough to proceed and keep in mind that things can still go wrong if you don't fully understand what your doing

i strongly suspect that you are doing or have done something which is causing your problem. you can leave it as is or take the system to a qualified repair shop and let them determine what's wrong and if they id the cause ask them to explain it to you

either choice is up to you, but since the z840 is not a cheap investment and/or you need the extra ram then paying a shop 50/75 dollars to resolve your issue is rather cheap compared to replacing the system

and i would like to point out that you have a WORKSTATION class system, not a consumer system 

i

[Dean512]

Nope, I simply tried to put a stick of ram into a computer and it made the computer fail...

Nothing really else going on...which is why I created the post to get an answer, and instead get this...I do thank you for “trying” to help. I just look to the future and do not try and figure out “why” sometimes, already costed me too much time. Thank you for your efforts in helping though, I do appreciate it.