Info Combining two DDR4 64GB kits is possible per my experience. What about DDR5?

[Numerous_Ruins]

Hi,

I've seen closed discussions here about combining memory kits and would like to provide my own experience. I combined two DDR4 64 GB memory kits in 2017 for a total of 128 GB RAM on an Asus Mark 2 X299 motherboard paired with an Intel Core I9-7900x. It has worked very well all these years with intense loads at times.

I am now considering combining two DDR5 96 GB kits for a total of 192 GB. My reason is two 96 GB kits is less expensive than one 192 GB kit. However has anyone tried this before? The 96 GB kits also operate at higher speeds. Perhaps stability would be compromised if the two kits are combined? I plan on getting a motherboard and CPU (MSI MEGZ790 GODLIKE E-ATX MOTHERBOARD paired with INTEL CORE I9-13900KS) that support these configurations.

Regards,

NR

 

[USAFRet]

Bottom line on mixing RAM:

There is no "100% always works".

Sometimes it works, sometimes it fails.

 

[Numerous_Ruins]

Bottom line on mixing RAM:

There is no "100% always works".

Sometimes it works, sometimes it fails.

Thanks for the reply. Note that I also combined the same memory in another workstation with the same hardware but different CPU: Core i7-7800X. That machine with 128 GB RAM has also been stable but not used as much as the i9 desktop.

 

[USAFRet]

Thanks for the reply. Note that I also combined the same memory in another workstation with the same hardware but different CPU: Core i7-7800X. That machine with 128 GB RAM has also been stable but not used as much as the i9 desktop.

And thats perfectly OK.
Your successes does not negate other peoples failures.

Recently, I combined a 2x 16GB set and 2x 32GB set of the same Corsair DDR4 RAM, and it failed.

 

[Numerous_Ruins]

And thats perfectly OK.
Your successes does not negate other peoples failures.

Recently, I combined a 2x 16GB set and 2x 32GB set of the same Corsair DDR4 RAM, and it failed.

Which motherboard?

 

[USAFRet]

Which motherboard?

B550M Aorus Pro

Corsair Vengeance LPX


Orig:
2x 16GB

Add:
2x 32GB

It boots up.
All 96GB recognized.

After a couple of minutes, ethernet cuts out.
Fully repeatable situation.

Each pair works fine on its own, in either slot pair.
Currently running the 2x 32GB.

 

[Numerous_Ruins]

B550M Aorus Pro

Corsair Vengeance LPX


Orig:
2x 16GB

Add:
2x 32GB

It boots up.
All 96GB recognized.

After a couple of minutes, ethernet cuts out.
Fully repeatable situation.

Each pair works fine on its own, in either slot pair.
Currently running the 2x 32GB.

Ok that's different. I never mixed various sizes. My X299 Mark 2 boards can take eight memory modules. I populated them all with identical 16 GB modules for a total of 128 GB in each computer.

I am tempted to order two 96 GB kits and also a 192 GB kit and see if it works. If there are issues I can try the 192 GB kit. The 96 GB kits are a little faster - DDR5 @ 5600 vs DDR5 @ 5200 for the 192 GB kit I realize the speed was reduced for stability with such a lot of memory. I think I'll contact Corsair to get their input also.

And I'll have to check the return policy before I proceed.

 

[Numerous_Ruins]

Update: I just purchased the 192 GB Corsair RGB kit and will pair it with a 13900KS. The CPU was expensive everywhere but I found a place that sells them in a tray configuration without a box for the Intel recommended price of $699. I've bought tray CPUs before without any issues. I am adding a Liquid Freezer II 420. Really stoked to build this. I also went with the Corsair 1000D Super Tower Case and will run two 3090s in it. The memory of the two 3090s can be pooled into 48 GB via NV Link and I hope it works as expected. The memory pooling is what I really care about since I do 3D renderings and have had some scenes that maxed out the 24 GB of a single 3090. A 4090 upgrade is therefore useless to me since Nvidia dropped NV Link support with the 4090. The only other option is a workstation GPU that's super expensive..