Noob question about RAM / number of sticks / MHz

[VelikiPCguy]

Hey all, for a top-end gaming PC (or even just in general), is it better to get more + smaller, or fewer + larger RAM sticks? Does it matter whether your motherboard is dual channel or quad channel for this (e.g. the Gigabyte X570 Aorus Master)?

 

Also, I've read that Ryzen CPUs (I'm thinking of getting the 5950X one) need to be manually overclocked to utilise more than 3200MHz of the RAM. Is that correct? Are there any downsides to, say, increasing it up to 4000MHz (if you've got sufficiently powerful RAM for it) in terms of stability, performance, or longevity?

 

Thanks!

[tkitch]

If you're overclocking, fewer sticks are easier to get timing down right with.  (So 2 sticks is better than 4 generally.)

The actual real world performance difference between 2 and 4?  Not really much outside of benchmarks.  (Of course, make sure you fill out your Mobo RAM Channels.  2 in dual, 4 in quad.)

[VelikiPCguy]

8 minutes ago, tkitch said:

If you're overclocking, fewer sticks are easier to get timing down right with.  (So 2 sticks is better than 4 generally.)

The actual real world performance difference between 2 and 4?  Not really much outside of benchmarks.  (Of course, make sure you fill out your Mobo RAM Channels.  2 in dual, 4 in quad.)

But even a dual mobo technically has 4 slots for the RAM sticks, so you're saying it's still better to use just 2?

 

And what about overclocking the CPU to get it above 3200MHz, is that a thing with Ryzen?

[tkitch]

3 minutes ago, NewwGuyy123 said:

But even a dual mobo technically has 4 slots for the RAM sticks, so you're saying it's still better to use just 2?

generally?  Yes.

[wONKEyeYEs]

17 minutes ago, NewwGuyy123 said:

Also, I've read that Ryzen CPUs (I'm thinking of getting the 5950X one) need to be manually overclocked to utilise more than 3200MHz of the RAM

I have a 5900x with Trident Z Neo DDR4-3600MHz and all I had to do was turn on XMP, it was basically plug'n'play.

[VelikiPCguy]

5 minutes ago, wONKEyeYEs said:

I have a 5900x with Trident Z Neo DDR4-3600MHz and all I had to do was turn on XMP, it was basically plug'n'play.

Ah ok, so you didn't have to do that whole thing where you select the GPU's ?channels? and set them each to 50% of your RAM's MHz, so that because there's two, they cover the full MHz of your RAM? I guess XMP just kind of has that all baked in?

[wONKEyeYEs]

3 minutes ago, NewwGuyy123 said:

Ah ok, so you didn't have to do that whole thing where you select the GPU's ?channels? and set them each to 50% of your RAM's MHz, so that because there's two, they cover the full MHz of your RAM? I guess XMP just kind of has that all baked in?

You're saying it wrong but yes, it's automatic for RAM and infinity fabric timings.

[Helpful Tech Witch]

5 minutes ago, NewwGuyy123 said:

Ah ok, so you didn't have to do that whole thing where you select the GPU's ?channels? and set them each to 50% of your RAM's MHz, so that because there's two, they cover the full MHz of your RAM? I guess XMP just kind of has that all baked in?

wht ius tyhis about gpus?

and what do you mwnt abot halving the speed?

[VelikiPCguy]

10 minutes ago, wONKEyeYEs said:

You're saying it wrong but yes, it's automatic for RAM and infinity fabric timings.

 

9 minutes ago, HelpfulTechWizard said:

wht ius tyhis about gpus?

and what do you mwnt abot halving the speed?

Sorry I'm trying to recall some half-baked info I picked up somewhere over the last few days that's jumbled up together with tonnes of other info re CPUs, GPUs, coolers, etc etc etc. Basically I (think) I read somewhere that to make your system (GPU? some other part?) "recognise" a RAM with more than 3200MHz, you'd have to manually do... something. I remember it having like two sides/part, so you only have to up each side/part by 50% of the MHz value (so 2000 for a 4000MHz RAM) and it would then be able to recognise it.

 

Haha sorry for the terrible explanation

[WoodenMarker]

1 minute ago, NewwGuyy123 said:

Sorry I'm trying to recall some half-baked info I picked up somewhere over the last few days that's jumbled up together with tonnes of other info re CPUs, GPUs, coolers, etc etc etc. Basically I (think) I read somewhere that to make your system (GPU? some other part?) "recognise" a RAM with more than 3200MHz, you'd have to manually do... something. I remember it having like two sides/part, so you only to up each side/part by 50% of the MHz value (so 2000 for a 4000MHz RAM) and it would then be able to recognise it.

If you enable XMP in the motherboard settings, you can load a preset for the RAM's advertised speeds. 

For example, if the kit is advertised to be 3200mhz CL15, enabling the XMP profile saves you the trouble of having to manually input the clock speed and timings. 

 

The 'double data rate' in DDR is using both edges of a clock to transmit data so the speed is effectively doubled. The speed that you'll see in the motherboard settings is this doubled clock speed but some software like CPU-Z may show half that. 

[Helpful Tech Witch]

5 minutes ago, NewwGuyy123 said:

 

Sorry I'm trying to recall some half-baked info I picked up somewhere over the last few days that's jumbled up together with tonnes of other info re CPUs, GPUs, coolers, etc etc etc. Basically I (think) I read somewhere that to make your system (GPU? some other part?) "recognise" a RAM with more than 3200MHz, you'd have to manually do... something. I remember it having like two sides/part, so you only have to up each side/part by 50% of the MHz value (so 2000 for a 4000MHz RAM) and it would then be able to recognise it.

 

Haha sorry for the terrible explanation

gpu and ram have nothing to do with eachother

the only thingd to do with ram and half is that really ddr is running at 1/2 the rated speed if you have xmp on (so 3200 is really 1600mhx) bc of ddr (double data rate). And that to have the best speed with ryzen you want infinity fabric to be half the ram speed. (so for 3200mhz ram you want 1600mhz infinity fabric)

[VelikiPCguy]

45 minutes ago, HelpfulTechWizard said:

gpu and ram have nothing to do with eachother

the only thingd to do with ram and half is that really ddr is running at 1/2 the rated speed if you have xmp on (so 3200 is really 1600mhx) bc of ddr (double data rate). And that to have the best speed with ryzen you want infinity fabric to be half the ram speed. (so for 3200mhz ram you want 1600mhz infinity fabric)

And enabling XMP does all of that?

[xg32]

1 hour ago, NewwGuyy123 said:

But even a dual mobo technically has 4 slots for the RAM sticks, so you're saying it's still better to use just 2?

 

And what about overclocking the CPU to get it above 3200MHz, is that a thing with Ryzen?

usually 4 sticks give better performance actually because it's dual rank, oc might be slightly lower but benches are higher, with zen 3 alot of imc and mobo can do 4x8 3600 just fine if you get the right sticks.

[VelikiPCguy]

1 minute ago, xg32 said:

usually 4 sticks give better performance actually because it's dual rank, oc might be slightly lower but benches are higher.

Haha whom do I trust!!

[xg32]

Just now, NewwGuyy123 said:

Haha whom do I trust!!

there are specific benchmarks for this from techtubers, hardware unboxed and gamer's nexus.

[VelikiPCguy]

8 minutes ago, xg32 said:

there are specific benchmarks for this from techtubers, hardware unboxed and gamer's nexus.

Ok so I've watched some stuff and it seems it primarily comes down to it being dual-rank. So sorry, just for my own sake, how do 4 single-rank RAMs produce a dual-rank configuration, but 2 single-rank RAMs don't?

 

And in one clip a guy even said 2 dual-rank sticks are better than 4 single-rank sticks, regardless of whether the 4 technically produce a dual-rank "configuration", cos they strain the IMC (whatever that is) less.

[VelikiPCguy]

11 minutes ago, xg32 said:

there are specific benchmarks for this from techtubers, hardware unboxed and gamer's nexus.

Also, sorry, how can you check whether a RAM stick you're looking at has single-rank or dual-rank, if it doesn't mention it in the description?

[Helpful Tech Witch]

1 hour ago, NewwGuyy123 said:

And enabling XMP does all of that?

xmp sets it to the timings and speed of the profile for the memory. Then if it matches teh infinity fabric it matches. if not, it doesnt mathc. (id change it yourself though, matching the infinity fabric is a big deal.