Same RAM, different sizes.

[Troy210]

Question:

If I have a 32GB RAM kit (2x16) and a 16GB RAM kit (2x8) I should be able to put them on the same motherboard, correct?

As long as they are the same speed, DDR4-3600 (which they are) and they go in the right slots?

Example, the 16GB sticks go in slots 1 & 3 - the 8GB sticks go in slots 2 & 4

Is that correct, or is old age finally taking a toll?

 

[dark2099]

Are the exactly the same kit, just different sizes, or no? If not, you'll either need to let them run the JEDEC specs (default, non xmp), or find out what main timings they can run together manually.

 

[oobymach]

They need to have the same timings for them to work afaik, so you may need to manually set timings.

 

[phanbuey]

It's an intel system so you can usually put whatever in there. Set the xmp to the 32GB kit and test for stability. Should be totally fine though.

 

[AusWolf]

As long as they are the same kit with the same speed and the same timings (primary and secondary), it should be fine.

I used to run an AMD FX system with two 2 GB and two 4 GB Kingston HyperX modules. Modern systems are even less hectic with RAM configuration.

 

[ir_cow]

It's an intel system so you can usually put whatever in there. Set the xmp to the 32GB kit and test for stability. Should be totally fine though.

idk if thats the best advice. The OP has a i7-8770K. You can put them all in, but don't expect XMP to work.

 

[phanbuey]

idk if thats the best advice. The OP has a i7-8770K. You can put them all in, but don't expect XMP to work.

It's probably an 8700K, since I'm not sure what an 8770K is. - which is the same system I had ~4 years or so ago, those IMCs are pretty forgiving, and if you have 2 kits rated the same, 99% of the time the higher density 32GB is the weaker kit, and you can force that XMP on the 16GB kit with no issues.

I did say test stability though, just to be sure. But I would be shocked if he had any issues.

Not to mention it's an MSI board - which those, z370/390 were great with ram.

 

[de.das.dude]

should be fine. i have successfully run slightly different timing as well as different sizes on my old system.

you may ned to play with the settings to find out which is the most stable. usually the slower timings of the two works well.

 

[izy]

On MSI motherboards you can try using Memory try it (or what is called, different vendors different name) with DDR4-3600 and hope that the motherboard will get the right timings.

 

[ir_cow]

It's probably an 8700K, since I'm not sure what an 8770K is. - which is the same system I had ~4 years or so ago, those IMCs are pretty forgiving, and if you have 2 kits rated the same, 99% of the time the higher density 32GB is the weaker kit, and you can force that XMP on the 16GB kit with no issues.

I did say test stability though, just to be sure. But I would be shocked if he had any issues.

Not to mention it's an MSI board - which those, z370/390 were great with ram.

Eh I disagree, 8th gen IMC isn't that strong. People struggled to get DDR4-4000 2x8GB stable lol. Only one way to find out. The OP already has the ram so what you gonna do...

 

[Troy210]

Slightly different timings.

Old kit currently installed: https://www.newegg.com/g-skill-16gb-288-pin-ddr4-sdram/p/N82E16820232194

New kit (not yet ordered): https://www.amazon.com/G-Skill-Trident-PC4-28800-CL18-22-22-42-F4-3600C18D-32GTZR/dp/B08176KLZT

 

[Athlonite]

That's easy just run the faster timed kit at the slower timing of the slower kit so that would be 18-22-22-42 test the shit out of it and if all is running ok then you're good to go

 

[ir_cow]

Slightly different timings.

Old kit currently installed: https://www.newegg.com/g-skill-16gb-288-pin-ddr4-sdram/p/N82E16820232194

New kit (not yet ordered): https://www.amazon.com/G-Skill-Trident-PC4-28800-CL18-22-22-42-F4-3600C18D-32GTZR/dp/B08176KLZT

The first kit is Samsung B-Die. Second is either Hynix or Samsung C-die is my best guess. Adding more ram from different kits isn't even the biggest issue. You are going into unknown territory. Single-rank plus dual rank kit, plus a older Intel generation. I don't think there will be issue with it booting at say 2133. Above that, its pure guesswork. Do what @Athlonite said and just stress test it to until your are satisfied. If it doesn't work, send it back. Should have 30-day return right?

 

[chrcoluk]

Definitely test the ram properly, my 8600k couldnt do over 3000mhz with 4 dimms populated.

 

[dgianstefani]

Bad idea to mix. If both were B die would be acceptable.

 

[Mussels]

Question:

If I have a 32GB RAM kit (2x16) and a 16GB RAM kit (2x8) I should be able to put them on the same motherboard, correct?

As long as they are the same speed, DDR4-3600 (which they are) and they go in the right slots?

Example, the 16GB sticks go in slots 1 & 3 - the 8GB sticks go in slots 2 & 4

Is that correct, or is old age finally taking a toll?

This should work fine, others have covered most of it

1. Voltages must match
2. Timings must match, but you can choose the slowest of any that differ or try overclocking.
2a. XMP and automatic settings may not work, or may read only from one kit of ram.
3. The number of ranks may differ - so you may have two dual rank and two single rank sticks for 6 ranks total. This wont affect much, but more ranks CAN increase performance while it WILL decrease overclocking.


In the end it's more or less like standard running four sticks of RAM - you may need to raise the overall RAM voltage, over-volt your memory controller, or manually tweak timings.

Can it work? Absolutely.
Is it guaranteed to work at high speeds? No.