[SOLVED] Question about using 4-DIMMs on Dual Channel

[julienruc]

Hi all,

This is my build:

PCPartPicker Part List

CPU: AMD - Ryzen 5 1600 3.2 GHz 6-Core Processor ($104.89 @ OutletPC)
Motherboard: Asus - STRIX B350-F GAMING ATX AM4 Motherboard ($124.89 @ OutletPC)
Memory: Corsair - Vengeance LPX 8 GB (2 x 4 GB) DDR4-3000 Memory
Storage: SanDisk - Z410 120 GB 2.5" Solid State Drive
Storage: Samsung - PM961 256 GB M.2-2280 Solid State Drive ($56.00 @ Amazon)
Video Card: MSI - GeForce GTX 1060 6GB 6 GB GT OCV1 Video Card ($349.36 @ OutletPC)
Case: Cooler Master - MasterBox Q500L ATX Mid Tower Case ($59.99 @ Amazon)
Power Supply: EVGA - BQ 600 W 80+ Bronze Certified Semi-modular ATX Power Supply ($77.28 @ OutletPC)
Case Fan: Deepcool - RF 120 (3 in 1) 56.5 CFM 120 mm Fans ($36.99 @ SuperBiiz)
Total: $809.40
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2019-07-12 04:40 EDT-0400

I to buy another set of 2x4Gb to upgrade to a total of 16Gb of RAM. I am planning on buying the EXACT same RAM sticks.

However, I've heard there were issues when trying to populate all 4 DIMM slots when using a motherboard that only supports Dual Channel at OC'ed speeds (like my motherboard). It says that doing this will default the RAM at stock speeds of 2400Mhz. Is this true or is there a workaround to this?

 

[CountMike]

There's no quad channel with 1st and 2nd gen Ryzen but 2 dual channels is possible with right combination and slot placement. Drawback is that it might not work as fast frequency as with only one IMC is used.

 

[julienruc]

There's no quad channel with 1st and 2nd gen Ryzen but 2 dual channels is possible with right combination and slot placement. Drawback is that it might not work as fast frequency as with only one IMC is used.

What does IMC mean?

When you say combination; what did you have in mind? Because I figured buying the exact same sticks would probably be the best route here?

 

[SkyNetRising]

When you say combination; what did you have in mind? Because I figured buying the exact same sticks would probably be the best route here?

Best route would be getting 2x8GB ram kit.
With 2 kits of 2x4GB you're taking a bit of gamble there.
It may work, may require manual tweaking of ram parameters in bios or may refuse to work altogether.
You will know only after you have tried it.

 

[CountMike]

What does IMC mean?

When you say combination; what did you have in mind? Because I figured buying the exact same sticks would probably be the best route here?

IMC = Internal Memory Controller that is in the CPU nowadays. Most have two of them so only 2 dual channels are possible.
When I say combination in this context is to put each pair in appropriate slots, most of time is B2 and A2 as primary and A1 and B1 as secondary if they are not as a set of 4 even if they are of same capacity.

 

[julienruc]

IMC = Internal Memory Controller that is in the CPU nowadays. Most have two of them so only 2 dual channels are possible.
When I say combination in this context is to put each pair in appropriate slots, most of time is B2 and A2 as primary and A1 and B1 as secondary if they are not as a set of 4 even if they are of same capacity.

IMC - I see.

Combination - Yeah for sure, was planing on doing that. But do you think I'll be able to run at OC speeds? Is double Dual Channel even a thing?

 

[julienruc]

Best route would be getting 2x8GB ram kit.
With 2 kits of 2x4GB you're taking a bit of gamble there.
It may work, may require manual tweaking of ram parameters in bios or may refuse to work altogether.
You will know only after you have tried it.

Seems like a waste of the 2x4 kit I already have but I was afraid this would be the case.

 

[julienruc]

Best route would be getting 2x8GB ram kit.
With 2 kits of 2x4GB you're taking a bit of gamble there.
It may work, may require manual tweaking of ram parameters in bios or may refuse to work altogether.
You will know only after you have tried it.

Seems like a waste of the 2x4 kit I already have but I was afraid this would be the case.

 

[SkyNetRising]

Not really a waste. You can have 2x8GB + 2x4GB this way (if this works and doesn't cause any issues).
If there are issues, you still get 16GB. 2x4GB kit can be used in a different system or sold.

 

[julienruc]

Not really a waste. You can have 2x8GB + 2x4GB this way (if this works and doesn't cause any issues).
If there are issues, you still get 16GB. 2x4GB kit can be used in a different system or sold.

Well hopefully I'll be able to sell it back. But do you know if there's a way for me to figure out if the config will work?

 

[SkyNetRising]

You will know only after you have tried it.

 

[julienruc]

Well the whole point of me asking here was to avoid having to try it myself as it's quite a lot of money just to "give it a try". I live in the countryside in France so my chances of selling the 2x4Gb sticks is quite low.

I posted here hoping somebody who knows more about RAM would know the answer to this confusing Dual Channel thing, which I'm having trouble understanding because the motherboard does have 4 DIMM slots. It would be a waste of money to have spent on 3000Mhz RAM if populating all 4 DIMM slots on a Dual Channel system defaults it to just 2400Mhz.