Division of Memory Usage Between Two RAM Cards

[Bernd Strauss]

Hello,

When two 4GB RAM cards are connected to the mainboard, and the system usually uses not more than 4GB, will the RAM in the second card be always empty? Or does the system equally divide the RAM usage between the two cards even if the memory usage is small?

 

[rgd1101]

You mean you running 32bit os on a 8GB system?

 

[rgd1101]

https://docs.microsoft.com/en-us/sysinternals/downloads/rammap
For definitions of the labels RAMMap uses as well as to learn about the physical-memory allocation algorithms used by the Windows memory manager, please see Windows Internals, 5^th^ Edition.

 

[USAFRet]

Hello,

When two 4GB RAM cards are connected to the mainboard, and the system usually uses not more than 4GB, will the RAM in the second card be always empty? Or does the system equally divide the RAM usage between the two cards even if the memory usage is small?

The system sees one big bucket of RAM, and uses as needed. It does not split between individual RAM sticks.

 

[TJ Hooker]

Assuming the two sticks were running in dual channel mode, limiting memory usage to one stick until it's full would actually reduce effective memory bandwidth and performance. So no.

 

[Solandri]

All of your RAM is always used. RAM not used by programs and the OS is used as a disk cache, because there's no point letting RAM sit there unused. If the system needs more RAM, it simply overwrites these disk cache pages.

 

[Bernd Strauss]

I am running 64-bit Windows 10 system on a 64-bit machine with 8GB RAM. I need to know whether the system splits the memory usage between the two RAM cards to make data processing faster. (This would be similar in principle to RAID 0 array for two hard drives.)

 

[USAFRet]

I am running 64-bit Windows 10 system on a 64-bit machine with 8GB RAM. I need to know whether the system splits the memory usage between the two RAM cards to make data processing faster. (This would be similar in principle to RAID 0 array for two hard drives.)

The OS sees whatever RAM is in there as one big bucket. It uses it as needed.
Now...2 x 4GB RAM on a dual channel board is a little bit faster than 1 x 8GB. But not "twice as fast".

And its a completely different concept than a RAID 0 with HDD's.

 

[TJ Hooker]

I am running 64-bit Windows 10 system on a 64-bit machine with 8GB RAM. I need to know whether the system splits the memory usage between the two RAM cards to make data processing faster. (This would be similar in principle to RAID 0 array for two hard drives.)

Yes, if your CPU has multiple memory channels (most mainstream CPUs have two), and you have one DIMM in each channel you will have increased memory bandwidth. So 2x4GB sticks in dual channel is faster than 1x8GB.

 

[Bernd Strauss]

Yes, if your CPU has multiple memory channels (most mainstream CPUs have two), and you have one DIMM in each channel you will have increased memory bandwidth. So 2x4GB sticks in dual channel is faster than 1x8GB.

Is it necessary to change some settings to make the system split memory usage between the RAM cards, or does the system do this by default?

 

[USAFRet]

Yes, if your CPU has multiple memory channels (most mainstream CPUs have two), and you have one DIMM in each channel you will have increased memory bandwidth. So 2x4GB sticks in dual channel is faster than 1x8GB.

Is it necessary to change some settings to make the system split memory usage between the RAM cards, or does the system do this by default?

All automatic.
No user intervention needed.