Laptop won't start after reboot when installed new RAM

[Tony_Kov]

Evidently, they haven't fixed the problem in the current BIOS.

Will it start with the one stick that was initially in the laptop and the second from HyperX set?

[litvcom]

Will work if I use SK Hynix + HyperX (8GB+8GB), but not quite correctly. On start at DDR4-2400, another at DDR4-2133. This problem for every owner of ProBook 4XX G5, but no one wants to fix anything. Awful support HP only proves that you do not need to buy their products anymore.

[Tony_Kov]

Just to clarify, SK Hynix is the one which was pre-installed in your laptop?

How did you know that one works at 2133, and the other at 2400? Also, which RAM works with which speed? 2133 - SK Hynix, 2400 - HyperX? 

I tried to run the following command from the command prompt:

 wmic MemoryChip get BankLabel, Capacity, Speed,  Manufacturer

It gives me 2400 on both slots, and also says that the default  8GB memory was manufactured by Samsung (CPU-Z gives the same information, part no. M471A1K43CB1. But it can happen that I indeed have the 2133 and 2400 too, but don't know how to determine it properly.

I will try to replace the original 8 GB with the other Kingston 16 GB RAM which is stated as compatible on Kingston's web-site,  will keep this thread updated (in about two weeks).

[litvcom]

"Just to clarify, SK Hynix is the one which was pre-installed in your laptop?"

Yes

"How did you know that one works at 2133, and the other at 2400? Also, which RAM works with which speed? 2133 - SK Hynix, 2400 - HyperX? "

I meant that since everyone works at 2133, and once 2400. If I use only SK Hynix - DDR4-2400, if + HyperX = random DDR4-2400 or DDR4-2133 (after reboot). If I use HyperX Kit 2x8 (HX424S14IB2K2/16) = "beeps".

P.S. I think the problem is that the BIOS does not support JEDEC/PnP or XMP Profiles.

[Tony_Kov]

So, how can you check the speed? In the task manager? Because mine always shows 2400.

Also, could you please copy JEDECs for both RAMs from CPU-Z?

Probably that will help to prove my idea about BIOS wrongly determining operating JEDEC profile at the boot (after reboot, more precisely). We will need only last four.

You can find JEDEC's in the CPU-Z, if you do as follows: 

1. Run CPU-Z.

2. In the bottom of the window there is "Tools" button ->  Save report as .TXT.

3. Open the report and find "JEDEC" in the text file.

Also you can look up the default RAM part no. here.

You can download CPU-Z from the developer (there is an option of zip-file which doesn't require installation):

https://www.cpuid.com/softwares/cpu-z.html

JEDECs for my RAM:

1. Samsung M471A1K43CB1 8 GB:

JEDEC #6 15.0-15-15-35-50 @ 1090 MHz
JEDEC #7 16.0-16-16-38-54 @ 1163 MHz
JEDEC #8 17.0-17-17-39-55 @ 1200 MHz
JEDEC #9 18.0-17-17-39-55 @ 1200 MHz

2.  Kingston KHX2400C14S4/16G

JEDEC #4 13.0-14-14-33-53 @ 1114 MHz
JEDEC #5 14.0-14-14-35-57 @ 1200 MHz
JEDEC #6 15.0-14-14-35-57 @ 1200 MHz
JEDEC #7 16.0-14-14-35-57 @ 1200 MHz

[litvcom]

"So, how can you check the speed? In the task manager? Because mine always shows 2400."

I check it on BIOS info and CPU-Z.

"Also, could you please copy JEDECs for both RAMs from CPU-Z?"

I can't, since I already use only SK Hynix DDR4-2400 and I want to return HyperX Kit. But if I'm not mistaken, the JEDECs is the same as yours.

[Tony_Kov · Accepted solution]

So, as promised, I update this thread again.

I replaced the default 8 GB with 16GB CL17 Kingston DDR4 while keeping the HyperX in its slot, and everything works fine after reboot.

Nevertheless, I will keep the default 8 GB with the new CL17 16 GB, and get rid of the HyperX set as it's rendered to be no use to this laptop.

I must conclude that as far as HP does not wish to do anything with this issue and provide compatibility with HyperX or any other fast memory, I will just close this thread with a warning message to anyone willing to try some hi-end RAM in HP ProBook G5 series laptops:

Do not buy any DDR4 2400 RAM with CL less than 17 - this laptop family at the moment does not support it and things are highly unlikely to change in the future.

[diaro561]

Wished I had seen this article before I bought myself 2x 16GB Kensington 2400 memories. I have an Elitebook 840 G5 that came with 2x 4GB 2400 .. like described above, my Notebook starts successfully after the new RAMs were mounted and everything works fine for as long as the device is not restarted / rebooted. After such reboot the memories are no longer accepted. This is particularly frustrating as no one can explain why it works first time then, after reboot, it does no longer. This lead me to believe HP is checking memory bricks after reboot and then, when they find any 3rd party bricks, reject from rebooting. The user manual also does not mention anything about this. 

[flappyberg]

Got the same problem but in an Asus GL753V Strix Laptop. Only black display except the existing 4gb Hynix ram. I tried different brands such as Kingston, Gskill, TeamGroup and Hynix with different frequencies and timings of 2400 and 2666 with CL17, CL16, CL18 but no good. Freshly installed OS, reset BIOS & updating BIOS doesn't solve the problem. 

[diaro561]

The problem can only be resolved by requesting exact compatible ram bricks. In my case I contacted Kingston and they've provided a list of RAM modules compatible to my laptop and also where to buy. No other chance. Neither HP nor Kingston provide a sound rationale why this is working first time but no longer after reboot. Note: even if one searches the internet with the correct product code does not guarantee one is getting a compatible (memory) product.