[SOLVED] Flex Mode vs Dual channel gaming

[gamer20088]

I just found out that this exists after buying 16 gig and 8 gig ram, they are same company and speed and latency and all but I will get worse performance? Should I refund and get 2x8 and wait 2 weeks for shipping?

 

[gamer20088]

If you want to return the modules you have to avoid any problems in the future you should do that, otherwise running the modules you have right now is only a problem if you use more than 16GB of ram. The 8GB and 16GB module will run in dual channel mode only up to 16GB (8+8GB) until you go over 16GB used ram.

So this is perfectly fine if I just game?

 

[Third-Eye]

So this is perfectly fine if I just game?

Yeah, but it will slow down and switch to single channel mode if you end up needing more than 16GB. Some games are not even adversely affected by single mode, so it may not even be an issue for you.

 

[gamer20088]

Yeah, but it will slow down and switch to single channel mode if you end up needing more than 16GB. Some games are not even adversely affected by single mode, so it may not even be an issue for you.

So say my game uses 8 gigs and I have 5 left in dual channel mode will it be dual channel?

 

[Karadjgne]

@Third-Eye
Depends on the ram. If you have 4gb in A2/B2 that'll work in dual channel, 2Gb + 2Gb. If you then put 4Gb stick in either of the 2 remaining slots, that'll still be dual channel, 2+2/4.


If you screw up the slots and sizes of ram don't match up, then you get 3x sticks in single channel. 2/2/4


Flex mode is just allowance of dual channel with a single channel leftover when 2 sticks are not the same size. Used to be you'd get both sticks in single channel only, as dual channel required same size, speed, timings and voltage but with flex that got changed to same speed, timings and voltage. Can't run flex with single or flex and dual, it's either single, dual or flex.

 

[gamer20088]

@Third-Eye
Depends on the ram. If you have 4gb in A2/B2 that'll work in dual channel, 2Gb + 2Gb. If you then put 4Gb stick in either of the 2 remaining slots, that'll still be dual channel, 2+2/4.


If you screw up the slots and sizes of ram don't match up, then you get 3x sticks in single channel. 2/2/4


Flex mode is just allowance of dual channel with a single channel leftover when 2 sticks are not the same size. Used to be you'd get both sticks in single channel only, as dual channel required same size, speed, timings and voltage but with flex that got changed to same speed, timings and voltage. Can't run flex with single or flex and dual, it's either single, dual or flex.

So if I put my 16 and 8 gig next to eachother I will have dual channel?

 

[Third-Eye]

So if I put my 16 and 8 gig next to eachother I will have dual channel?

No, two modules need to be in separate channels (A and B) and on your motherboard they should be in slots 2 and 1, with 1 being the furthest slot from the CPU socket. |CPU Socket| |4|2|3|1|

 

[gamer20088]

No, two modules need to be in separate channels (A and B) and on your motherboard they should be in slots 2 and 1, with 1 being the furthest slot from the CPU socket. |CPU Socket| |4|2|3|1|

Finally thank you this was my first time with ram and I now know everything! I can keep my ram!

 

[Karadjgne]

You need ram in A2 and B2 with Ryzens, that's slot #2 and #4 if you start at the cpu side. Those are the primary slots. If you use the secondary slots, #1 and #3, it's doubtful you'll get higher speeds than 2666MHz/2933MHz as those slots are basically purposed for 4 stick use.

It's ¦cpu¦ 3 1 4 2 DIMM (A1, A2, B1, B2) for almost every board. Some Asus boards (Asus Crosshair is one) have changed that up, and their sockets read B1, B2, A1, A2 which translates to ¦cpu¦ 4,2,3,1 DIMM.

If using one of those Asus boards, (you'll need to check the user manual) then you'd still use slots #2 and slot #4, which is still B2/A2 as specified by Amd. A2 is the primary slot for Ryzen use with a single stick, in most boards its slot #2 (DIMM 1), but on those few odd Asus boards you'd use slot #4 (DIMM 1) instead.

 

[gamer20088]

You need ram in A2 and B2 with Ryzens, that's slot #2 and #4 if you start at the cpu side. Those are the primary slots. If you use the secondary slots, #1 and #3, it's doubtful you'll get higher speeds than 2666MHz/2933MHz as those slots are basically purposed for 4 stick use.

It's ¦cpu¦ 3 1 4 2 DIMM (A1, A2, B1, B2) for almost every board. Some Asus boards (Asus Crosshair is one) have changed that up, and their sockets read B1, B2, A1, A2 which translates to ¦cpu¦ 4,2,3,1 DIMM.

If using one of those Asus boards, (you'll need to check the user manual) then you'd still use slots #2 and slot #4, which is still B2/A2 as specified by Amd. A2 is the primary slot for Ryzen use with a single stick, in most boards its slot #2 (DIMM 1), but on those few odd Asus boards you'd use slot #4 (DIMM 1) instead.

Thank you for the explanation!

 

[Karadjgne]

Yeah, dunno why asus did that, it's been the same cpu-a-b for years, then a few boards are backwards. It would make sense if just using 1 stick of ram, because then even the biggest cpu coolers wouldn't be an issue, none of them reach that last slot. However, who in their right mind would ever decide to run such an expensive mobo, probably with a giant cpu to require the largest coolers... And only use 1 stick of ram. If using 2 sticks for standard dual channel, you still use #2/#4, same as always, same cooler issues.

 

[gamer20088]

Yeah, dunno why asus did that, it's been the same cpu-a-b for years, then a few boards are backwards. It would make sense if just using 1 stick of ram, because then even the biggest cpu coolers wouldn't be an issue, none of them reach that last slot. However, who in their right mind would ever decide to run such an expensive mobo, probably with a giant cpu to require the largest coolers... And only use 1 stick of ram. If using 2 sticks for standard dual channel, you still use #2/#4, same as always, same cooler issues.

Got it