2x32 or 4x16GB is better for RAM?

So I'm looking into what setup is better, 2x32 or 4x16 DDR5 and I've seen varying comments.

The general consensus appears to give 2x32 the edge, or 2x whatever, v filling up all four channels, but it's not definitive.

There are comments about single rank v dual rank, and some seem to favour the latter while others say the latter is slower than single.

So I have 4x16 single rank @ C40 6000Mhz v 2x32 dual rank C32 @ 6000.

What would be the stronger choice?

 

It's easier for the memory controller to run just 2 dimms. This allows for higher clocks and lower timings.
Regarding ranks, the best setup is to have 4 ranks. 2 ranks, has lower performance. 8 ranks is much harder for the memory controller to drive.

So the ideal situation is a 2x32GB, dual rank kit.

But if you already have the memory, and its working well, there is not much point in switching.
The gains are not that big.

 

You wont be running same freq. with 2 or 4 dimms. 4x16gb is alot harder on imc.

 

Depends on task?

 

With 4x16 you will have dual rank config as with 2x32. So the better timings should decide the winner.

 

Thanks for the replies here, currently I have 4x16 TeamDelta 6400 (@6000) DDR5 @ C40 single rank, and 2x32 G.skill dual rank 6400 (@6000) C32.

I got the latter because I was hoping to get the full 6400 because the board QVL said it would work at that speed but it peaks out at 6000 before I get issues.

And the consensus here seems to be the g.skill is my favoured option. I'd agree. I have it in there and performance is good. I understand single rank is meant to be quicker but I saw a site claiming all four channels filled is the best option.

Both work @ 6000, and seems you guys are saying timings win the day.

 

I miss the days of tripple and quad channel enthusiast platforms.

As for op: I'd go 2 DIMMs, the best you can get / run with your CPU / MB.

 

That`s false assumption. At least for DDR4. I don`t know whether DDR5 brings something completely new...

https://forums.guru3d.com/threads/single-rank-vs-dual-rank-ram-just-in-case.447117/

 

It's half right.
Single rank kits can usually clock a bit higher. But this doesn't make up for the advantage of the memory controller being able to access more ranks, in dual rank configurations.
It's the same for DDR 4 and DDR5.

 

When one plank is dual rank, but when you populate all two slots per channel with single rank planks does it introduce dual rank config? (That was my original assumption here.)

 

It's just that the more ranks, the harder it is for the memory controller to drive the kits.

 

Why?

 

Because it has to coordinate accesses throughout more memory ranks.
You have to consider that memory is very dumb. So the memory controller has to do all the work.

 

I see. According to videos I have seen so far memory controllers learned to utilize 2 ranks quite good

 

Up to 4 ranks, most memory controllers work very well. Although they do lose a small percentage of clock speed.
It's only when we go to 8 ranks, that there is a stronger loss in speed.

 

(Let`s continue discussion.)
Why the loss of clock speed?
Do you mean that two ranked planks has lesser MHz by default? Or do you mean that two ranked planks do not work at claimed MHz?

 

The memory controller can't clock memory as high the more ranks it uses.
But it's just a very small diference.

 

Are you sure? (I am not trolling, I am just wrestling fuller answers from you...)

PS Does memory controller feed actual clock signal to modules? Or motherboard does that?

 

How don't know exactly the inner workings of this. Just the experience me and many other overlockers have.
I think buildzoid explained this in one of his videos about ranks.

 

I am curious because clock signal is just a sync thing, as I take it. I see no reason to lower sync signal because of two ranks. Controller takes into account the presence of several ranks to choose them for increased parallelism, but all ranks should be able to work with same sync signal.

And again, one thing is a plank with two ranks on it, and another thing is two single ranked planks in one channel slots.

PS And overclock is not in question in this thread. If plank is rated at certain MHz it should not matter whether single ranked or not.