Question 64GB DDR4 installed but 31.9GB useable. How to solve this?

[SroyC]

Hello all.
I do not know how long I have been going through this problem. The first time I installed 32GB (16GBx2) with my previous 32GB (16GBx2) I could see 64GB usable. Lately, I started getting BSOD while working with my Ps. Just by chance, I discovered in the system information that RAM is half. I am enclosing screenshots for your reference.

I use W10 64bit OS.

I cannot use the 64GB installed RAM, only 31.9GB is usable according to the OS. Please note, that I have enabled XMP Profile 1 (the only XMP profile available) in the BIOS. I tried to swap the RAM sticks but that did not help. I have tried the first two RAM slots keeping the other two empty. In this case, the OS shows 32GB without any usage restriction. When I attach the other two RAM sticks to slots 3 and 4 on the MB, it shows 31.9 GB usable, though the installed RAM capacity is 64 GB.

Here are some pre-checks I have done:

1. Does the memory capacity show 64GB in bios?

Yes, it shows 4 memory sticks of 16GB each installed.

2. Did the user try to use two memory sticks to install memory DDR4_1 and DDR4_2 slot?

If 16GBx2 sticks are installed in A1 and A2, then the system shows 32GB usable and 32GB installed. Installing 2x16GB sticks in B1 and B2 only, keeping A1 and A2 empty does not boot the system, which I believe is a feature of this motherboard. I have only DDR4 sticks.

3. Manual page 10 for dual channel installed.

I followed this. I am enclosing the link to the manual for your reference.

4. Install one RAM individually into each slots to check if the problem cause from specific slot.

I tried it. Please refer to the 2nd answer above.

5. Use another functional memory model to check if possible.

I do not have any other, but I swapped the sticks and those are fine till 32GB is installed.

6. Load optimized defaults setting in bios and clear CMOS.

I tried it. It disables the XMP Profile 1 in BIOS.

7. Update to latest bios F52 to check.

I have done it, but it does not solve the problem.

8. RAM Part number, capacity and brands?

All are 16GB DDR4 sticks with the same part number and from Corsair.

Brand:	Corsair
Size:	4x16GB
Memory Part No.:	CMK16GX4M1E3200C16

Please help me to resolve this issue. I am unable to use my image editing programs optimally as the usable RAM is not enough for speedy use.


Screenshots:

 

[Aeacus]

You have 32.1 GB as Hardware Reserved, indicating that the new 2x 16GB set will not play ball with old 2x 16GB set.

Hardware reserved RAM tends to be a problem with the physical RAM, the RAM slots or the CPU. The BIOS may well detect all 64 GB but if there is an issue, the RAM will be marked reserved as it can not be accessed.

The first time I installed 32GB (16GBx2) with my previous 32GB (16GBx2) I could see 64GB usable.

Mixing memory is bad idea.
Why?
Further reading (especially 2nd chapter "mixed memory").
link: https://forums.tomshardware.com/faq...y-ram-and-xmp-profile-configurations.3398926/

That being said, your RAM, CMK16GX4M1E3200C16, is not included in your MoBo memory QVL list, at all. So, there is no guarantee that it has to work. There are only few 3200 Mhz kits listed, none of the Corsair 16GB kits will work when all 4 slots are populated. Only one of the Corsair 3200 Mhz kits, 4GB DIMMs (16GB in total) works on all 4 slots.

So, for fixes;
1. Buy a kit of 4x 16GB RAM, if you want a guarantee that all of it works together.
2. Pick a kit from the MoBo memory QVL list for an additional guarantee.

You can download memory QVL from here,
link: https://www.gigabyte.com/Motherboard/GA-AX370-Gaming-K3-rev-10/support#support-doc
Pick the "For Pinnacle Ridge support" file since that's what your CPU is.

E.g 64GB set that Gigabyte has confirmed to work in all 4 slots in your MoBo are;
3000 Mhz:
HX430C15PB3K4/64 (HyperX)
CMU32GX4M2C3000C15 (Corsair)
F4-3000C14Q2-128GVKD (G.Skill)

2933 Mhz:
CMK128GX4M8Z2933C16 ver 4.31 (Corsair)

2800 Mhz:
CMD32GX4M2B2800C14 (Corsair)
etc. (more options in memory QVL)

 

[Lutfij]

The first time I installed 32GB (16GBx2) with my previous 32GB (16GBx2) I could see 64GB usable. Lately, I started getting BSOD while working with my Ps.
+
CMK16GX4M1E3200C16
You should pull all sticks of ram from your build and see what the PCB revisions are on the sticks of ram.

You're currently on BIOS version F51g;
https://www.gigabyte.com/Motherboard/GA-AX370-Gaming-K3-rev-10/support#support-dl-bios
flash to version F52 and then clear the CMOS.

 

[thestryker]

If 16GBx2 sticks are installed in A1 and A2, then the system shows 32GB usable and 32GB installed. Installing 2x16GB sticks in B1 and B2 only, keeping A1 and A2 empty does not boot the system, which I believe is a feature of this motherboard. I have only DDR4 sticks.

If the manual you linked is the right one then it's DIMM 1-4 so what do you mean by A1/A2 and B1/B2?

If you're talking about the two separate memory channels then you have a memory channel which isn't working.

I tried it. It disables the XMP Profile 1 in BIOS.

Does it show 64GB correctly without the XMP profile enabled?

If it does then your CPU's memory controller cannot handle 3200 which wouldn't necessarily be surprising since Zen+ was real hit and miss with memory controllers. Should this be the case try clocking it down to 2933 and see if that works.

If nothing resolves how it's showing up then you can try removing the CPU and reseating it making sure there's no socket damage, pin damage and that the mounting tension is good. If this doesn't work then it's likely a CPU or motherboard problem and the only way to troubleshoot would be with other hardware: your CPU in a different, known working, board or a different, known working, CPU in your board.

 

[geofelt]

Two ram kits with the same part number are not matched.
The construction underneath may be totally different.
Each kit may have different xmp settings to give the advertised performance.
Past that, ryzen is very sensitive to ram compatibility and managing 4 sticks is much harder than two.

What to do??

1. Return what you can and replace with a 64gb kit that is explicitly supported on your cpu/mobo combo.
Either the mobo ram qvl list or the ram vendor support list.

2. There is a possibility you can get things to work by manually entering ram settings for speed, timings, and voltage.
Likely the speed will need to be lower and the voltage higher.

 

[helper800]

These are the only supported 64gb kits for that motherboard from G Skill. Notice that they are all 2133-2666 M/Ts? That is because when you start pushing the limit with RAM density on 4 sticks you cannot run the RAM as fast and stay stable.