Dual/Single rank clarification

[Whosonicus]

So I'm planning to buy the same RAM model I have in my PC, resulting in 16GB ram for my multitasking needs on a Ryzen 3 1300x

My question; is dual rank memory the act of using 2 sticks of RAM on a PC? or are the sticks actually designed differently?

 

Curious

[mariushm]

No, dual rank and single rank refers to how the tiny memory chips are wired on the memory stick, how they communicate with the processor.

 

What you're thinking of is Dual Channel, which is automatically activated when you put at least one memory stick in each channel available on your motherboard.

If your motherboard has only two memory slots, then each slot will be one channel. If the motherboard has 4 slots, see manual (usually channels are colored differently)

 

Dual rank memory sticks are a tiny bit harder to work with (by the cpu and motherboard) so it's possible to not be able to reach very high frequencies, especially when 4 memory sticks are installed.

For example, a cheaper motherboard may only be able to run 4 memory sticks at 2933 Mhz or 3000 Mhz even though the sticks are sold as 3200 Mhz (or more).

Single rank memory sticks can often be overclocked easier and can reach higher frequencies.

 

As a general idea, 4 GB DDR4 sticks are pretty much always single rank, and 8 GB sticks are probably 25-40% single rank, and the rest are double rank - the higher end ones, higher frequency ones. more expensive ones are often single rank.

 

16GB or higher sticks are pretty much always dual rank.

 

[Whosonicus]

3 hours ago, mariushm said:

No, dual rank and single rank refers to how the tiny memory chips are wired on the memory stick, how they communicate with the processor.

 

What you're thinking of is Dual Channel, which is automatically activated when you put at least one memory stick in each channel available on your motherboard.

If your motherboard has only two memory slots, then each slot will be one channel. If the motherboard has 4 slots, see manual (usually channels are colored differently)

 

Dual rank memory sticks are a tiny bit harder to work with (by the cpu and motherboard) so it's possible to not be able to reach very high frequencies, especially when 4 memory sticks are installed.

For example, a cheaper motherboard may only be able to run 4 memory sticks at 2933 Mhz or 3000 Mhz even though the sticks are sold as 3200 Mhz (or more).

Single rank memory sticks can often be overclocked easier and can reach higher frequencies.

 

As a general idea, 4 GB DDR4 sticks are pretty much always single rank, and 8 GB sticks are probably 25-40% single rank, and the rest are double rank - the higher end ones, higher frequency ones. more expensive ones are often single rank.

 

16GB or higher sticks are pretty much always dual rank.

 

 

So is it dual rank or dual channel that benefits Ryzen CPU’s (according to internet)?

[nick name]

Just now, Whosonicus said:

 

So is it dual rank or dual channel that benefits Ryzen CPU’s (according to internet)?

Dual rank can help, but it's dual channel that the internet is talking about.  

 

Dural rank is RAM chips on both sides of the RAM stick.  Single rank is RAM chips on one side of the RAM stick.  

[mariushm]

3 minutes ago, nick name said:

Dural rank is RAM chips on both sides of the RAM stick.  Single rank is RAM chips on one side of the RAM stick.  

Position of the chips on the stick has nothing to do with dual rank or single rank - it's not a rule.  It is true most sticks that have chips on both sides are dual rank, but it's not obligatory.

[nick name]

5 minutes ago, mariushm said:

Position of the chips on the stick has nothing to do with dual rank or single rank - it's not a rule.  It is true most sticks that have chips on both sides are dual rank, but it's not obligatory.

You're absolutely correct.  Forgive me.