Ram upgrade problem Elitebook 840 G5

[h4ckman]

Hi, i bought HP Elitebook 840 G5 (SN: [edited]) with 8GB DDR4 2400Mhz sodimm ram memory. I want to upgrade it to the max, and bought brand new Kingston HyperX 32gb Kit (2x16GB DDR4 - 2400Mhz) (HX424S14IBK2/32). After upgrade everything works fine, and my system says that i have 32GB of RAM, and I can use it regulary for hours. But, when i shut down or restart my Elitebook, it wont turn on again. It beeps like there is RAM problem, and my numlock and capslock are blinking at the same time. When I repeat the proces, same thing happens. Now, i use Samsung 8GB that came with laptop, and i dont have any problems. In Serbia i cant find Samsung memmory, and my local dealer offering me Adata ram memory which is poor quality as i know. Please help, i use my Elitebook all day long, and memory utilization is over 95% most of the time... Sorry for my bad english...

[Huffer]

Is it the 7th or 8th gen version? This kind of illustrates what can happen when you install memory other than specified modules especially if you are trying to max out the machine. There is no advantage to be had from Hyper-X or other performance or gaming memory and it will have more aggressive timings. The specified modules are:

16-GB 865396-850

This is CL=17 and the memory you installed is CL=14. 

Specified memory is SK Hynix:

SK Hynix SO-DIMM 16GB DDR4-2400-S HMA82GS6AFR8N-UH

Post back with any more questions and please accept as solution if its the info you needed. 

[h4ckman]

I have Core I7 8550U. My local HP dealer told me that smaller the latency is, memory is faster... So, if I buy CL17 will it resolve my problem? On the official page there is no other info about ram exept this: sodimm DDR4/2400MHz , 32GB max... 

[Huffer]

The part number I listed above is from the official Maintenance and Service Manual for your laptop and the specs I quoted and the memory type is what you get if you order that kind of memory by that part number. Lower latency memory can be faster, but only if the motherboard supports the lower latency. In this case it does not. The Hyper-X is being clocked to the same specs as OEM memory and the HyperX does not like that it seems. 

[h4ckman]

Ok, ty for that info. Ill try CL17 and hope it will work. 

[Huffer]

Not just any CL17 try to find the Hynix or Samsung. 

[ivgeo42]

I have the exact same issue, but I got it to work on an HP Ultraslim Docking Station.

[knet_alex]

Hi H4ckman. I have the same exact problem as you had. After replacing memory kit, first boot is OK. after restarting notebook wont turn on again. Beebs a blink.

I made BIOS update to the latest one (01.09.01 Rev.A) with the original HP memory, and after update I tried to install the HyperX memory Kit. update doesn't solved the problem 😞

partial solution: If you combine the original HP memory with one of the Kingston Hyper X, than notebook start normally (even after several restarts). 

Than I've checked through CPUZ app Memory info, and it show

it is definitely not the solution of the problem.

For info the 32GB (16+16) HyperX kit info: