Question Unable to register RAM in DIMMA1/DIMMB1 (second RAM lane)

linuxdeveloper.io

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I have a brand new MSI MPG B550 Gaming Plus motherboard, which is working great, except for the fact I can't get it to register more than 32GB of RAM. It should support up to 64GB.

I have 2x 16GB Corsair (https://www.amazon.nl/dp/B01CYILUB8/) sticks which work great in DIMMA2/DIMMB2 and show up as 32GB.

If I put 2 more sticks of the same module in the second RAM lane (DIMMA2/DIMMB2) it fails to boot, and the motherboard debug light is stuck on CPU.

I have tried rotating the RAM in all the combinations and I still can't get it to boot with more than 32GB of RAM.

The debug light seems to indicate that there is a problem with the CPU. I have tried loosening up the CPU cooler by a half-turn to see if their was a bad connection on one of the pins, but no luck.

I thought maybe there was a setting in the BIOS to enable the 2nd lane of RAM but I can't find any such setting. I also flashed the latest BIOS to the motherboard.

Is the 2nd memory controller/lane just broken on this CPU? (AMD Ryzen 5 5600X).

Any other options to debug or is this simply a bad CPU/motherboard?

Thanks in advance.
 
I have 2x 16GB Corsair (https://www.amazon.nl/dp/B01CYILUB8/) sticks which work great in DIMMA2/DIMMB2 and show up as 32GB.

If I put 2 more sticks of the same module in the second RAM lane (DIMMA2/DIMMB2) it fails to boot, and the motherboard debug light is stuck on CPU.

I have tried rotating the RAM in all the combinations and I still can't get it to boot with more than 32GB of RAM.

The debug light seems to indicate that there is a problem with the CPU. I have tried loosening up the CPU cooler by a half-turn to see if their was a bad connection on one of the pins, but no luck.

You are mixing RAM which is never a good idea.
Return what you have and get a single kit (4x16) at 3200Mhz preferably with Samsung B-Die chips and CL14

Reason being that modules are binned after manufacture to match Latency.
Manufacturers warn of this due to the slight variations in Latency/Density of the Silicon in their chips.
This is a common problem and although in some cases the system may boot however random reboots and shutdowns unexpectedly occur and in many cases will not past Post.
 
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linuxdeveloper.io

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You are mixing RAM which is never a good idea.
Return what you have and get a single kit (4x16) at 3200Mhz preferably with Samsung B-Die chips and CL14

Reason being that modules are binned after manufacture to match Latency.
Manufacturers warn of this due to the slight variations in Latency/Density of the Silicon in their chips.
This is a common problem and although in some cases the system may boot however random reboots and shutdowns unexpectedly occur and in many cases will not past Post.

Ah, thank you... I thought you only had to match the RAM in each RAM lane 1 and 2.

That makes more sense now why 2x16gb kit is $135 and 4x16gb kit is $700.
 
Ah, thank you... I thought you only had to match the RAM in each RAM lane 1 and 2.

That makes more sense now why 2x16gb kit is $135 and 4x16gb kit is $700.

Your CPU has a built in memory controller and it can get confused with Dimm's that don't match especially Ryzen infinity fabric.

Corsair Vengeance (4x16) 2666MHz are $257 from Newegg
Corsair Vengeance (4x16) 3200 MHz are $390 from Newegg

I can recommend G.Skill - F4-3200C14D-64GTZR for $379 from Newegg.
They are a superior RAM at C14.



 

linuxdeveloper.io

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Your CPU has a built in memory controller and it can get confused with Dimm's that don't match especially Ryzen infinity fabric.

Corsair Vengeance (4x16) 2666MHz are $257 from Newegg
Corsair Vengeance (4x16) 3200 MHz are $390 from Newegg

I can recommend G.Skill - F4-3200C14D-64GTZR for $379 from Newegg.
They are a superior RAM at C14.

I miss the low prices of newegg. I am in Europe, so I only checked amazon.nl, which is where I saw the high prices.

Looking on tweakers.net now and I see megekko.nl has it for 259 euro. I am going to pick one of these up and see if it works.

https://www.megekko.nl/product/0/1102002/Corsair-DDR4-Vengeance-LPX-4x16GB-3200

Good reminder to do price comparison against evil amazon.
 

linuxdeveloper.io

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I installed the new 3200mhz ram with 64gb (matched from one new pack) and it wouldn't boot. It has the motherboard debug LED lit up with CPU. I then tried with just 32gb and the same thing happened -- wouldn't boot and stuck on CPU led.
None of the new ram worked.

I then installed the old 2400mhz ram with 32gb, and it booted fine.

Very confused.
 
I installed the new 3200mhz ram with 64gb (matched from one new pack) and it wouldn't boot. It has the motherboard debug LED lit up with CPU. I then tried with just 32gb and the same thing happened -- wouldn't boot and stuck on CPU led.
None of the new ram worked.

I then installed the old 2400mhz ram with 32gb, and it booted fine.

Very confused.
Have you ever checked if all these kits (old and new) are on the QVL for you motherboard ? If they were tested and how many DIMMs worked together ?
https://www.msi.com/Motherboard/MPG-B550-GAMING-PLUS/support#mem

Given the problems you encounter, I wonder if it would be wise to stick with tested solutions.
 

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Motherboard BIOS up to date?

Corsair RAM doesn't run very well with Ryzen is my experience, especially with 4 sticks. Better use 2x32GB like https://tweakers.net/pricewatch/1729294/kingston-fury-renegade-kf432c16rbk2-64.html or https://tweakers.net/pricewatch/1502220/g-punt-skill-ripjaws-v-f4-3200c16d-64gvk.html

Motherboard BIOS is up to date.

Have you ever checked if all these kits (old and new) are on the QVL for you motherboard ? If they were tested and how many DIMMs worked together ?
https://www.msi.com/Motherboard/MPG-B550-GAMING-PLUS/support#mem

Given the problems you encounter, I wonder if it would be wise to stick with tested solutions.

I do not see Corsair 2400mhz or 3200mhz, although I do see a lot of other Corsair skus. I will try with a tested solution and report back.
 
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I installed the new 3200mhz ram with 64gb (matched from one new pack) and it wouldn't boot. It has the motherboard debug LED lit up with CPU. I then tried with just 32gb and the same thing happened -- wouldn't boot and stuck on CPU led.
None of the new ram worked.

I then installed the old 2400mhz ram with 32gb, and it booted fine.

Very confused.
Did you set BIOS to default before installing new RAM?
 

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I installed the Kingston 2x32GB kit in the DIMMA2/DIMMB2 slots, and again same error - the debug light on the motherboard stays stuck lit on "CPU". I put the original Corsair 2x16gb kit back in and it booted up fine.

It seems like the CPU cannot handle more than 32gb of RAM. Disappointing, especially the $900 in RAM I spent trying to debug this. Oh well.
 
Go into bios and load bios defaults.
Save and exit.
After reboot shut down computer.
Turn off or unplug power supply.
Press the power/start button to drain capacitors.
Remove bios battery.
Short CMOS reset jumper pins or button for at least 15 seconds.
This is a hard bios reset. It removes ALL bios settings. It also removes memory training information it stores.
Replace battery and CMOS jumper to correct position.
Install memory and boot computer.
Do not expect it to boot right away.
It needs to Memory train again.
It could take several minutes and may restart a few times while doing so.