Need advice on going for 4 dimms or 2 dimms

[Atriox]

I want to run my ram at 6000mhz, but currently I use 4 dimms.

I have heard that it’s not possible to do this, but I wanted to check before sending back the ram.

I am using Corsair Dominator Titanium and X870e Crosshair Hero and plan to use 4x16GB with a 9800x3D.

Would you advise that I send the sticks back and get 2x32 or will it be fine when using AMD EXPO?

[_I_]

you can always change ram (when the pc is off *not standby/sleep)

but first reset bios to defaults or disable xmp so that it puts the ram speeds/timings/voltage to stock so it will post with the new ram

most boards detect different ram, and go back to default ram settings, but sometimes they dont and may take a few failed boots before it will post with it

but if it was a 4x dimm kit, you can just pull out 2 dimms while the pc is off and it will be fine

if its within the return time period you can return/exchange the ram from where you purchased it
only in extremely rare cases can you rma ram for another dimm/kit

[C1REX]

I would advice to change it to 2x32.
4 sticks are way more difficult to run. That may lead to stability problems or higher voltage on memory controller what may or may not cause problems in a long run.

[BurakZG]

There is no simple answer to your question. (Like "it will work" or "it will not work" with the speed you want).
RAM in the PC is not element that "works with some speed". It is an element that "aceepts the speed and timings" from motherborad and the processor.
The processor that you want to run with (AMD 9800X3D) has offcially max speed 2x DDR5-5600 or 4x DDR5-3600
Even if you buy 2x 32GB 6000 it might still not work with that speed. It will work so, only if you are lucky and your processor/motherboard are able to work with this settings as well. Less RAM sticks make your chances bigger.
Take the timings (CL) into account. It is as much important as MT speed.

[smokerob79]

you will be fine....DDR5 does not have the same problems DDR4 did.....4 sticks is fine on the platform.....now the real question comes to play....will the memory work with the motherboard......

[Atriox]

smokerob79 lähetti viestin:

you will be fine....DDR5 does not have the same problems DDR4 did.....4 sticks is fine on the platform.....now the real question comes to play....will the memory work with the motherboard......

I dunno about that - I have been having issues with my current PC on DDR5 for the past year now and it turns out the reason why I was getting so many crashes is because I had 4 dimms set to 6000mhz. I took 2 dimms out and now the PC no longer has issues.

I have decided to order 2 x 32 Ram sticks at 6000mhz which will be stable.

[Illusion of Progress]

If you want to increase your chances of achieving 6,000 MHz, go with less DIMMs if you have that choice.

If single DIMMs don't exist in high enough capacities that get you the total capacity you need, then you're going to have to accept you'll need to make a frequency tradeoff, especially on DDR5. 64 GB+ (can be done with two DIMMs, but needs dual rank) may need slight concessions, and 128 GB+ (where you need four DIMMs regardless) needs real concessions.

But you say you're already using 4x 16 GB DIMMs. What RAM generation, and what platform? If you're already doing this on DDR5 and AM5 specifically, I would default to trying it first since you already have it and therefore have nothing to lose.

6,000 MHz is very uncommon on DDR5, at least with AM5 (it's a bit more likely on an Intel 700 series chipset with Raptor Lake specifically), but it's not entirely impossible. It's just rare enough that you'd never recommend someone to expect it, again especially on AM5, and even those who try it often find they're not sure if they're entirely stable.

People will often tell you expect closer to the 4,800 MHz to 5,200 MHz window (maybe 5,600 MHz if you're lucky and the DIMMs are single rank), with four DIMMs.

smokerob79 lähetti viestin:

you will be fine....DDR5 does not have the same problems DDR4 did.....4 sticks is fine on the platform.....now the real question comes to play....will the memory work with the motherboard......

DDR5 is worse here.

You always have a lower maximum speed you can stabilize when you you do any of the following...

1. Add more DIMMs
2. Use DIMMs with more ranks

This is a universal truth, and DDR5 is not exclusive to this. It's actually worse at this for a variety of factors. Being 2x 32-bit internally instead of 1x 64-bit may be part of why, and it's simply trying to run at much higher frequencies, so these variables come into play even more

It's getting worse as time goes on. Why do you think CPU and motherboard manufacturers have started listing the maximum RAM speed supported with a breakdown in recent years, instead of a single supported speed, such as...

2x1R DDR4-3200
2x2R DDR4-3200
4x1R DDR4-2933
4x2R DDR4-2667

That first bit is the DIMM and rank count, because those things, plus frequency (and motherboard and its BIOS), are what determines if you will stabilize a given speed.

They are using conservative values versus what you are likely to achieve, yes (the above is for a late AMD DDR4 CPU, not DDR5), but you are not likely to achieve 6,000 MHz on AM5 with four DIMMs. Even if it's single rank. And dual rank 32 GB DIMMs exist, so why would you intentionally choose 4x 16 GB DIMMs over that anyway?

[Atriox]

Illusion of Progress lähetti viestin:

If you want to increase your chances of achieving 6,000 MHz, go with less DIMMs if you have that choice.

If single DIMMs don't exist in high enough capacities that get you the total capacity you need, then you're going to have to accept you'll need to make a frequency tradeoff, especially on DDR5. 64 GB+ (can be done with two DIMMs, but needs dual rank) may need slight concessions, and 128 GB+ (where you need four DIMMs regardless) needs real concessions.

But you say you're already using 4x 16 GB DIMMs. What RAM generation, and what platform? If you're already doing this on DDR5 and AM5 specifically, I would default to trying it first since you already have it and therefore have nothing to lose.

6,000 MHz is very uncommon on DDR5, at least with AM5 (it's a bit more likely on an Intel 700 series chipset with Raptor Lake specifically), but it's not entirely impossible. It's just rare enough that you'd never recommend someone to expect it, again especially on AM5, and even those who try it often find they're not sure if they're entirely stable.

People will often tell you expect closer to the 4,800 MHz to 5,200 MHz window (maybe 5,600 MHz if you're lucky and the DIMMs are single rank), with four DIMMs.

smokerob79 lähetti viestin:

you will be fine....DDR5 does not have the same problems DDR4 did.....4 sticks is fine on the platform.....now the real question comes to play....will the memory work with the motherboard......

DDR5 is worse here.

You always have a lower maximum speed you can stabilize when you you do any of the following...

1. Add more DIMMs
2. Use DIMMs with more ranks

This is a universal truth, and DDR5 is not exclusive to this. It's actually worse at this for a variety of factors. Being 2x 32-bit internally instead of 1x 64-bit may be part of why, and it's simply trying to run at much higher frequencies, so these variables come into play even more

It's getting worse as time goes on. Why do you think CPU and motherboard manufacturers have started listing the maximum RAM speed supported with a breakdown in recent years, instead of a single supported speed, such as...

2x1R DDR4-3200
2x2R DDR4-3200
4x1R DDR4-2933
4x2R DDR4-2667

That first bit is the DIMM and rank count, because those things, plus frequency (and motherboard and its BIOS), are what determines if you will stabilize a given speed.

They are using conservative values versus what you are likely to achieve, yes (the above is for a late AMD DDR4 CPU, not DDR5), but you are not likely to achieve 6,000 MHz on AM5 with four DIMMs. Even if it's single rank. And dual rank 32 GB DIMMs exist, so why would you intentionally choose 4x 16 GB DIMMs over that anyway?

Luckily the recommended speed for 9800x3D is 6000Mhz on two dimms. I’m getting an x870e crosshair hero next with Corsair Dominator Titanium so 2x32 at 6000mhz EXPO should be more than stable.

[Illusion of Progress]

Unless you're really unlucky, then 6,000 MHz should almost always work on AM5 with two DIMMs if the RAM itself and motherboard aren't terrible. With luck on the IMC/CPU side, you might be able to do a bit higher and get 6,400 MHz, but I'm not sure how likely that is on dual rank DIMMs (32 GB DIMMs will be dual rank). You'd need to win some luck on the silicon lottery with the IMC either way, but as long as you get 6,000 MHz then it's fine enough.

[Atriox]

Illusion of Progress lähetti viestin:

Unless you're really unlucky, then 6,000 MHz should almost always work on AM5 with two DIMMs if the RAM itself and motherboard aren't terrible. With luck on the IMC/CPU side, you might be able to do a bit higher and get 6,400 MHz, but I'm not sure how likely that is on dual rank DIMMs (32 GB DIMMs will be dual rank). You'd need to win some luck on the silicon lottery with the IMC either way, but as long as you get 6,000 MHz then it's fine enough.

Looking at Hardware Unboxed’s video, anything above 6000 is pretty much pointless.

Thank you for the reassurance about 6000mhz with two dimms - I’m going to use an x870e Crosshair Hero and Corsair Dominator Titanium 2x32GB.

[GOD RAYS ON ULTRA™]

You're going to want four dimms to avoid static interference. You only use two rams on two dimm motherboards. The empty slots cause issues.

https://www.tomshardware.com/pc-components/ram/empty-ram-slots-can-harm-dram-performance-asus-nitropath-slots-curb-electrical-interference-gain-400-mt-s-and-are-40-percent-shorter

This is why you always populate all dimms.

[r.linder]

GOD RAYS ON ULTRA™ lähetti viestin:

You're going to want four dimms to avoid static interference. You only use two rams on two dimm motherboards. The empty slots cause issues.

https://www.tomshardware.com/pc-components/ram/empty-ram-slots-can-harm-dram-performance-asus-nitropath-slots-curb-electrical-interference-gain-400-mt-s-and-are-40-percent-shorter

This is why you always populate all dimms.

Use dummy modules to eliminate the noise while still not overstressing the IMC.

[Illusion of Progress]

GOD RAYS ON ULTRA™ lähetti viestin:

You're going to want four dimms to avoid static interference. You only use two rams on two dimm motherboards. The empty slots cause issues.

https://www.tomshardware.com/pc-components/ram/empty-ram-slots-can-harm-dram-performance-asus-nitropath-slots-curb-electrical-interference-gain-400-mt-s-and-are-40-percent-shorter

This is why you always populate all dimms.

That "issue" it causes is "it's harder to stabilize as a result of that added interference".

But here's the thing. Using four DIMMs on four slot motherboards are still harder to stabilize than two DIMMs on a four slot motherboard. And the real world results prove it; you will stabilize higher speeds on two DIMMs than on four DIMMs. So the electrical interference doesn't matter more than DIMM count does (unless you go against motherboard manufacturer recommendations and use slots A1 and B1 instead of A2 and B2).

That's like pulling your eye out to say "I avoided a poke in the eye". Sure, it's technically true... but you're still worse off for it anyway.

Better actual end results > arbitrary factors.

Of course, the best results would be two found on two DIMM slot motherboards, but uh... you're really limiting your choice selection then. And on AM5, once you start getting above 6,000 MHz, you're often limited by the IMC silicon lottery anyway so it doesn't matter if you have extra headroom on the motherboard side if you don't need it.

You should get four DIMMs only if you have high capacity needs that force you into it getting that many DIMMs in order to reach your desired capacity. This is coming from someone with four DIMMs (and for that reason).

[_I_]

^ this

harder for the cpus imc to hit higher freq with 4 dimms
vs harder for the board to hit higher freq with 2 dimms

holding 6000+ is near impossible with 4 dimms anyway, saying 4 dimms can be slightly more stable just due to the boards design is pointless when its limited by the cpus imc

[Atriox]

Illusion of Progress lähetti viestin:

GOD RAYS ON ULTRA™ lähetti viestin:

You're going to want four dimms to avoid static interference. You only use two rams on two dimm motherboards. The empty slots cause issues.

https://www.tomshardware.com/pc-components/ram/empty-ram-slots-can-harm-dram-performance-asus-nitropath-slots-curb-electrical-interference-gain-400-mt-s-and-are-40-percent-shorter

This is why you always populate all dimms.

That "issue" it causes is "it's harder to stabilize as a result of that added interference".

But here's the thing. Using four DIMMs on four slot motherboards are still harder to stabilize than two DIMMs on a four slot motherboard. And the real world results prove it; you will stabilize higher speeds on two DIMMs than on four DIMMs. So the electrical interference doesn't matter more than DIMM count does (unless you go against motherboard manufacturer recommendations and use slots A1 and B1 instead of A2 and B2).

That's like pulling your eye out to say "I avoided a poke in the eye". Sure, it's technically true... but you're still worse off for it anyway.

Better actual end results > arbitrary factors.

Of course, the best results would be two found on two DIMM slot motherboards, but uh... you're really limiting your choice selection then. And on AM5, once you start getting above 6,000 MHz, you're often limited by the IMC silicon lottery anyway so it doesn't matter if you have extra headroom on the motherboard side if you don't need it.

You should get four DIMMs only if you have high capacity needs that force you into it getting that many DIMMs in order to reach your desired capacity. This is coming from someone with four DIMMs (and for that reason).

Yeah it just sounds like flawed logic coming from them. As you said, 2 dimms is still going to be a lot easier to stabilise than 4 dimms because of how sensitive CPUs are.

I’m going for 2x32 sticks so that I have the same ram size as what I do now but with two sticks. Things are good these days though, I’ve seen options for 48GB sticks so I don’t see much point in going for 4 sticks anymore unless you’re not doing gaming and instead doing productivity related tasks.

[r.linder]

Hence why dummy modules are useful, the article they linked even talks about it, servers often use them