Dual Channel Memory

[kd5]

Howdy folks, been awhile.

 

My question:

 

Always before, in order for memory to be dual channel, there had to be 2 equal size/type sticks of memory in the proper slots. I now have an ASUS laptop with 4gb soldered to the motherboard, and another 4gb stick (replaceable). The laptop will hold a max of 12gb of memory, but I suspect that if I swap that 4gb stick out for an 8gb stick, it will no longer be dual channel. Is this still true? Am I also correct in assuming that even though I'll have more memory, the fact that it is no longer dual channel means memory performance will take a hit?

Thanks for any insight,

 

-kd5-

[nigsy]

Hi;

 

Wasn't sure; but found this:

 

https://serverfault.com/questions/912283/can-mixing-ram-memory-size-on-its-own-reduce-dual-channel-performance/912298

 

Think it explains it pretty well. I guess the question is - Does your Motherboard support Flex mode?

[kd5]

According to CPU-Z, it's a ASUS X712DAP motherboard w/ a Ryzen 3 processor, Radeon graphics.  I've done some preliminary research on the presence of Flex mode on this motherboard and found nothing useful...

[Tx Redneck]

Hola @kd5 Long time no see! I hate how OEMs are soldering components to the mobo like that these days. 

 

I've not dealt with this either, so am of no help, but

 

Tx

[kd5]

Yep, it's been awhile.  Real sorry to hear about Y.  When did this place change to PC Matic?  I know it's the name of the software, but the forum too?

[nigsy]

On 2/19/2021 at 12:06 PM, kd5 said:

Flex mode on this motherboard and found nothing useful...

 

I've been looking into this as it sparked an interest in something I didn't know. From what I can see Flex mode is automatically enabled on any MOB when mixed RAM is used. The BIOS will report 'Memory Running in Flexmode' at POST.

 

It seems unless you're benchmarking or OCing real world loss of speed by not running in Dual Channel Vs Flex seems to be limited.

 

 

[Tx Redneck]

On 2/19/2021 at 6:13 PM, kd5 said:

Yep, it's been awhile.  Real sorry to hear about Y.  When did this place change to PC Matic?  I know it's the name of the software, but the forum too?

We rebranded last year to bring it in line with the company and product name.

 

Tx

[Tx Redneck]

@kd5this just popped up the tubes of you and is 100% relevant to your situation. @nigsyI'd never heard of this flex mode you posted about, till your post, and this vid references it directly.

 

Tx

 

 

[nigsy]

@Tx Redneck Interesting stuff - It's been a while since I messed with RAM timings but I always found slowing the faster rated sticks down slightly and increasing the slower stick up to match 'in the middle' always worked best.

Like I mentioned to KD5, in the real world I don't think you'll notice any difference if you get the configuration right.

 

Interesting video though.