[SOLVED] 3200 Ram works in Single Channel but only 2133 in Dual Channel

Sparky812

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Mar 2, 2010
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CPU: Ryzen 1800X
MOBO: Gigabyte AB-350 Gaming
RAM: DDR4 34200Mhz - G.Skills F4-3200C14-16GFX

Hi Folks,
This has been driving me bananas for weeks.
When I put the 2 sticks of Ram in Slots A1 and B1 (single channel) . XMP profile works fine. They run at 3200MHz, Windows 10 sees 16gb, Task manager sees 16Gb running at 3200Mhz. CPU-Z recognizes single channel at 1600Mhz.

When I put RAM in Slots A1 and A2 or B1 and B2 (dual channel) XMP looks OK but Windows says 16gb (7.95 usable), Task manager sees 8 Gb@2400Mhz and CPU-Z shows dual channel at 1064MHz.

I have latest BIOS update and checked all QVLs, everything looks compatible.

I've also tried with various pairs of 3200 RAM and have the same issue so I'm assuming it must be a MOBO or maybe CPU issue? Do I need to overclock CPU to get this Ram to work?

Any help would be appreciated.
 
Solution
this is a 1st gen AM4 motherboard, XMP will not necessarily work even with b-die Samsungs. you may be limited to 2933Mhz in dual channel no matter what you try

Sparky812

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The speed supported by your motherboard will vary by the processor installed.
Your 1800X summit ridge processor does not appear to support any speed past 2400 on the ram support list:
https://download.gigabyte.com/FileList/Memory/mb_memory_ga-ab350-gaming.pdf

Sorry, my RAM is listed right in the 3200MHZ section ( 4th one down) of that QVL.
It runs at 3200 Mhz in single channel so why not dual?
If it were limited to 2400 why would it run at 1064MHz and not at 1200Mhz per channel?
 
Sorry, my RAM is listed right in the 3200MHZ section ( 4th one down) of that QVL.
It runs at 3200 Mhz in single channel so why not dual?
If it were limited to 2400 why would it run at 1064MHz and not at 1200Mhz per channel?
My bad, I see it now.
I suggest you contact g.skil to see what they say.
In anticipation, test each stick individually with memtest86.
First at stock, then at 3200 speed.
It boots from a usb stick and does not use windows.
You can download the free edition here:
https://www.memtest86.com/download.htm
 

Sparky812

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I did contact G.Skill ... got this response. Tried suggestions... no difference.



Make sure modules are firmly inserted. Did you test each one to see if they recognize as 8GB?

The memory should be installed in slots two and four away from the CPU.

You may need to reinstall Windows to see if it can work better.

In some cases checking CPU socket pins and reinstalling CPU can help. Let us know how it goes.

Thank you
GSKILL SUPPORT


Wondering if I need to bump CPU memory clock or maybe voltages?