PC won't recognize RAM > 32GB

[chutney the crab]

I have gotten a Workstation from work as a bonus, and am trying to upgrade it to 128 GB RAM.

 

CPU: Intel Core i9 9900K, 3,6 Ghz

Mainboard: ASUSTeK WS Z390 PRO

BIOS Version: 1102 (Updated 11/27/2020)

Not sure if any other specs matter, it has a 1000W PSU and a GPU.

 

It came with 2x 16GB No-Name Memory Modules, running properly in Dual Channel.

I checked and both the CPU and the Mainboard (updated to the latest BIOS) should support 128 GB RAM.

 

So I bought a new RAM Kit (HyperX Predator 3600MHz DDR4 (4x32GB)). I know I won't benefit from the extra speed with the older hardware, but I'll be able to re-use it down the line...

 

As the PC is kind of an awkward build, the CPU cooler is blocking one of the RAM slots, I started off trying out 2 sticks.

Installed them, booted up... and still had only 32 GB RAM, instead of 64.

 

I then performed the following tests:

• Tried out both new RAM stick individually. Each works and gives me (obviously) 32 total.
• Tried out one of the sticks in the each slot + the 3rd free slot individually. It universally works fine, giving me 32 GB.
• I added one of the old No-Name 16GB sticks in combination (2x32 in the Dual Channel slots, 1x16 in the extra slot). Still 32 GB instead of 80.

I don't want to remove the CPU cooler until I am reasonably sure I can actually use the RAM, but I don't see how the 4th slot would give me extra data work off of.

 

In every case, the OS only recognized 32GB and tools like CPU-Z shows a single populated "Slot" despite 2 sticks being in there right now.

 

Really appreciate any and all input

[CustomEnchants]

In your BIOS is your full 128gb detected ?

[chutney the crab]

4 minutes ago, CustomEnchants said:

In your BIOS is your full 128gb detected ?

Nope, it is not. It only ever recognizes 32 GB during boot-up.

[fuzz0r]

I might be looking at the wrong one, but I don't think so.

Where did you read that the motherboard supports 128GB?

[Tegneren]

I cant find that RAM set on the QVL for your motherboard, so it might be that that specific set is not working for that motherboard.

The QVL however does not mean only the listed sets work, only that those specific sets are proven to work properly.

 

[Tegneren]

4 minutes ago, fuzz0r said:

I might be looking at the wrong one, but I don't think so.

Where did you read that the motherboard supports 128GB?

I think your'e looking at the wrong specs

from this page: https://www.asus.com/Commercial-Servers-Workstations/WS-Z390-PRO/specifications/

[chutney the crab]

30 minutes ago, fuzz0r said:

I might be looking at the wrong one, but I don't think so.

Where did you read that the motherboard supports 128GB?

As Tegneren pointed out, there may be separate spec sheets floating around. I believe it may be related to a BIOS update they made, enabling the extra RAM...

 

27 minutes ago, Tegneren said:

I cant find that RAM set on the QVL for your motherboard, so it might be that that specific set is not working for that motherboard.

The QVL however does not mean only the listed sets work, only that those specific sets are proven to work properly.

 

That would be a real pity (and serves me right for not taking it seriously. I was under the impression that this stuff is not as finicky) That being said, would it then not simply fail completely, instead of capping out oddly at exactly 32GB?

[Tegneren]

3 minutes ago, chutney the crab said:

As Tegneren pointed out, there may be separate spec sheets floating around. I believe it may be related to a BIOS update they made, enabling the extra RAM...

 

That would be a real pity (and serves me right for not taking it seriously. I was under the impression that this stuff is not as finicky) That being said, would it then not simply fail completely, instead of capping out oddly at exactly 32GB?

Yeah, its a bit strange, but it might be it just cant cope with more than one stick at a time when its that particular set, no matter what the other sticks are. I dont know.

[Kilrah]

Did you clear CMOS yet? And don't enable XMP or do any RAM tweaking for now.