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Any problem mixing 2*32 & 2*48GB DDR5 modules?

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System Name Dirt Sheep | Silent Sheep
Processor i5-2400 | 13900K (-0.02mV offset)
Motherboard Asus P8H67-M LE | Gigabyte AERO Z690-G, bios F29e Intel baseline
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I now have Corsair Vengeance 2*32GB DDR5 5200Mhz C40 (CMK64GX5M2B5200C40) and in need of more (heavy projects and many Adobe prog running at the same time). I want to get 2*48GB 5200 C38 (CMK96GX5M2B5200C38) to max my slot capacity. 160GB total.

Any reason to have problems with those mix modules?
 
You will need to run the slower timings for compatibility, so possibly no AMP/XMP/DOCP
 
So a drop to JEDEC memory spec (4800MHz) because of C40 vs C38?
 
Mixing is never a good idea. Even worse is 48GB and 16GB DIMMs together. They have different primary and sub-timings.

Depending on the platform (AMD or Intel), you may not be able to reach the desired XMP/EXPO frequency. Just don't do it.

Edit: it will probably work at DDR5-3600 without issues.
 
If they didn't come in the same kit, it ain't a hit. I do not mix as you can introduce stability issues.
 
Ok, thanks all.
I will go with the exact same kit and 128GB will need to be enough.
 
Ok, thanks all.
I will go with the exact same kit and 128GB will need to be enough.
What people meant to say, is RAM has a huge number of timing parameters. They won't match for non-matching kits and motherboards are rather unlikely to detect and apply the proper settings by themselves. But if you have the time, you can find the least common denominator on your own. Failing that, they're supposed to work at standard JEDEC timings (I believe JEDEC goes all the way to 6400 these days, but don't quote me on that).
 
I you mix different RAM, music will be... MiXeD

:peace:
 
4x dual-rank on 12/13th Intel is better vs AMD Ryzen 7000. Going by your specs you have a 13th gen CPU. Just understand that it will be hard to reach DDR5-5600. Probably be around 4800 or 5200.
 
4x dual-rank on 12/13th Intel is better vs AMD Ryzen 7000. Going by your specs you have a 13th gen CPU. Just understand that it will be hard to reach DDR5-5600. Probably be around 4800 or 5200.
Yes, I knew about that speed "limitation" with 4x dual rank. Hance I choose 5200 in the first place, plus the work I do doesn't really gain from fast RAM. I also go with z690 as it enough for that RAM speed.

I didn't think I will need to add ram so quickly but even so, price come down nicely in the past 6 month so I'll get another identical set and be done with it.
 
Yes, I knew about that speed "limitation" with 4x dual rank. Hance I choose 5200 in the first place, plus the work I do doesn't really gain from fast RAM. I also go with z690 as it enough for that RAM speed.

I didn't think I will need to add ram so quickly but even so, price come down nicely in the past 6 month so I'll get another identical set and be done with it.

If you can afford the downtime, why not sell your existing kit and pick up a full 128 or 192 GB kit? You can probably get $150 for your kit, Corsair's 5200 192 GB kit goes for $550 or so but you should be set for a very long time if you need so much RAM. That would turn out to like $300 or so to spend.
 
Did AMD (or Intel) ever clearly state that mixing 24/48 GB modules with 16/32 GB ones is even possible? If not, I'd lean towards "no". I mean, these combination might be completely incompatible with existing bioses or even existing memory controllers, regardless of speed and timings.
 
If you know what you're doing, 0 problems.

if you don't, it can be an headache.

If you are familiar with timmings and sub timmings and how memory works you can make anything work.


Did AMD (or Intel) ever clearly state that mixing 24/48 GB modules with 16/32 GB ones is even possible? If not, I'd lean towards "no". I mean, these combination might be completely incompatible with existing bioses or even existing memory controllers, regardless of speed and timings.

nonsense. theres no such thing as "incompatible combinations with bioses"
 
nonsense. theres no such thing as "incompatible combinations with bioses"
Well, up until recently, BIOSes did not support 24MB RAM sticks... So there can be such thing.
 
Thats just something they do to protect them from liability
What they did was add the ram to the qlc list, that doesn't mean that said ram didnt work before..

If it's ram and fits the slot, it WILL work, it might run with crap timmings, sub and frequency, but it'll run.
 
If it's ram and fits the slot, it WILL work, it might run with crap timmings, sub and frequency, but it'll run.
Sorry, but I disagree here. First off you need the newest BIOS for 24/38GB DIMm support, secondly your mixing dual and single rank with different types of ICs. Different voltage requirements and timings (plus sub-timings). Just asking for stability issues if you are mixing.
 
Thats just something they do to protect them from liability
What they did was add the ram to the qlc list, that doesn't mean that said ram didnt work before..
Since I haven't tried those modules with a BIOS that didn't support them, I wouldn't know. Have you?
If it's ram and fits the slot, it WILL work, it might run with crap timmings, sub and frequency, but it'll run.
That's what I said, also. But not everybody will have patience/time to fiddle with all the timings some mobos expose. It should work using JEDEC timings, but even that might not be a guarantee, if the modules aren't properly QAed.
 
If you can afford the downtime, why not sell your existing kit and pick up a full 128 or 192 GB kit? You can probably get $150 for your kit, Corsair's 5200 192 GB kit goes for $550 or so but you should be set for a very long time if you need so much RAM. That would turn out to like $300 or so to spend.
Selling is too much hassle for me right now and 192gb from go at 700$+ if I'm not mistaken. 128gb will be enough I guess.
Maybe in the future 4x64GB will be available. This setup is here for the long 10 years+ run.
What people meant to say, is RAM has a huge number of timing parameters. They won't match for non-matching kits and motherboards are rather unlikely to detect and apply the proper settings by themselves. But if you have the time, you can find the least common denominator on your own. Failing that, they're supposed to work at standard JEDEC timings (I believe JEDEC goes all the way to 6400 these days, but don't quote me on that).
I know about, but don't understand, all the RAM timing shenanigans.
This is an editing PC, not a test setup and I need stability above all. Best practices is to keep it simple and stay on the yellow brick road.
 
Maybe in the future 4x64GB will be available.
When 32 Gb dies become available. I haven't seen any news recently about plans to introduce them. Looks like the 24 Gb dies are here to stay for quite a long time.
 
Sorry, but I disagree here. First off you need the newest BIOS for 24/38GB DIMm support, secondly your mixing dual and single rank with different types of ICs. Different voltage requirements and timings (plus sub-timings). Just asking for stability issues if you are mixing.

i'm dumb, for some reason though this was talking about ddr4.

And you're right, mixing dual rank with single rank is asking for problems but it is possible, in the past i managed to stabilize 4 sticks from different ic's and single and dual rank.
It took me a long time and a LOT of headache but I managed to do it.

Can't really recommend if the word fun is not associated with memory oc. :laugh:
 
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Did you update the BIOS or anything you can think of?
 
Did you update the BIOS or anything you can think of?
No, but it POST with JEDAC 4800MHz and recognized all 128GB. I detailed it all in the new thread. Please continue over there.
 
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