MSI x870 Tomahawk EXPO not working

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derekfoster1971262029b

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Hi all, I recently bought the x870 Tomahawk with Ryzen 9950x and a 64 GB Ram Kit (2x 32gb sticks): Corsair cmk64gx5m2b6000z30. I am on the latest A16 beta bios and whenever I enable the EXPO setting the board fails to boot with A6 motherboard code - the RAM is rated at CL30 6000MHz. I have tried many different settings (EXPO on/off while manually setting 6000Mhz and lower speeds etc.) but nothing works. Also had MCR and Power down off and on but the system will only boot with the RAM at its default 4800 MHz CL40 speeds.
Any suggestions on how to get the RAM working at advertised speeds on this board would be greatly appreciated.
Thanks!
 
Solution
M
expo actually means overclocking

expo ram is "certified" to run at expo profile settings
cpu is "cerfified" to run at amd spec DDR5-5600
mainboards should be able to run the memory as stated in the QVL documentation (if the memory kit is not present in the QVL prepare for surprises)

so if you have problems with expo memory the percentages must be split like this

40% unlucky IMC (or other cpu related problem, mounting pressure for example)
30% unlucky ram kit (sometimes the memory needs a small tweak to run at expo values)
30% unlucky mb (defective memory lanes, very common on ddr5 motherboards, with no vendor exceptions)

this is why support have to answer like that
"in theory" the cpu is more likely to be the problem because...
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Hi, guys. Same issues here.

Setup: MSI MAG X870 Tomahawk WiFi + Ryzen 9950x + CMK64GX5M2B6000C30.
BIOS: E7E51AMSI.1A40
It worked for some days, but with some freezing issues. Some days ago, it just went way worse, at the freeze happened more often until the motherboard always showed the error code C5, EC, or 0d.

I removed the RAM from the B2. It worked with the A2 alone. Test both the sticks on A2 alone and it work too. A1 + A2 also works. MemTest86 passed too. The problem sounds to be on double channel or B-channel. A2 + B2 doesn't work. B1 + B2 doesn't work. B2 alone doesn't work. Sometimes the A2 + B2 after the A2 alone work, but it freezes sometime after the Windows boot and the C5/EC starts again.

I will ask the seller to exchange it for a KF560C30BBEK2-64. Wish me luck.
 
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gt.katakur15af02e7 said:
Hi, guys. Same issues here.

Setup: MSI MAG X870 Tomahawk WiFi + Ryzen 9950x + CMK64GX5M2B6000C30.
BIOS: E7E51AMSI.1A40
It worked for some days, but with some freezing issues. Some days ago, it just went way worse, at the freeze happened more often until the motherboard always showed the error code C5, EC, or 0d.

I removed the RAM from the B2. It worked with the A2 alone. Test both the sticks on A2 alone and it work too. A1 + A2 also works. MemTest86 passed too. The problem sounds to be on double channel or B-channel. A2 + B2 doesn't work. B1 + B2 doesn't work. B2 alone doesn't work. Sometimes the A2 + B2 after the A2 alone work, but it freezes sometime after the Windows boot and the C5/EC starts again.

I will ask the seller to exchange it for a KF560C30BBEK2-64. Wish me luck.
Click to expand...
What do you mean by freeze issues... Does it stuck and a reset is needed or is it just for one second?
 
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fewele310161602ee said:
Does the system work with EXPO On if you reduce DRAM Frequency to 5600 Mhz and also lower the DRAM Voltage, DRAM VDDQ Voltage and CPU VDDIO Voltage to 1.25v?
Click to expand...
The PC was working at EXPO 6000mhz at A1 + A2, and it worked at 5600mhz, but I disabled the EXPO because of some comments on this forum. I was concerned that it would damage the CPU. I saw some comments from you saying that, too. Do you think that the EXPO could damage the CPU? That's why after 1 week of use, the A2 + B2 no longer works? It already arrived configured this way with the EXPO + 6000mhz.

On the BIOS, the Core Voltage shows 1.386 (it is auto on the configuration, just floating around 1.37~1.38 on BIOS interface). Should I lower it? I am a newbie at these things, never trying to change any voltage on any PC piece.
 

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I am also concerned with EXPO Voltages potentially degrading/damaging CPU faster and reducing its lifespan faster so i want to see these features added to Bios if possible. https://forum-en.msi.com/index.php?...-to-see-in-msi-bios-if-it-is-possible.412386/

What CPU VCore Voltage you will get i think depends a lot on silicon quality. Higher VCore Voltage probably means lower silicon quality so CPU needs higher VCore voltage to be stable or it can mean higher silicon quality and CPU can tolerate higher VCore Voltage better. Those who have lower VCore Voltage in Bios can also probably mean it can't handle higher VCore Voltage and CPU can degrade faster or it can mean they got silicon lottery and can overclock better to get higher performance.

You can try Negative Curve Optimizer to try to Undervolt Core Voltage somewhat. Start with 05 and slowly raise 10, 15, 20, 25, 30 until its unstable in Cinebench and choose the number CPU is fully stable. It is also possible CPU will be unstable at only 05 which means you can't Undervolt CPU and it can be only stable at stock.
 
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Just sharing the default motherboard voltages with these configurations:
- EXPO off + Default 3600MHz
- EXPO off + Manually selected 4800MHz
- EXPO on + Manually selected 5600MHz

The RAM is currently running in slots A1 + A2. I didn’t have time to test A2 + B2 today.

I appreciate the guidance for fine-tuning, but I’ve already spent too much time on this, and it’s cutting into my work hours. I’ll need to work over the weekend to make up for the lost time. For now, I’ll keep it at EXPO off (default 3600MHz) until the seller decides whether to send a replacement RAM kit or request the PC for further analysis.

I’m also concerned about potential CPU damage. Should I ask the seller to replace the Ryzen 9 9950X as well? Do you think MSI’s default configurations could have harmed the CPU within just one week of use?
 

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Your CPU NB/Soc Voltage is high when EXPO is on, it needs to be 1.2v and should not exceed 1.25v. Maybe it will stop freezing and throwing errors if you manually set it to 1.2v.

You could also try this RAM in Slots A2 and B2: https://www.gskill.com/specification/165/396/1731653457/F5-6000J3036F48GX2-FX5-Specification
It runs at 5600 Mhz by default and uses 1.10v without EXPO so you wont have to worry about CPU VDDIO voltage potentially degrading CPU.
If you turn on EXPO, it will run at 6000 Mhz and use 1.35v EXPO voltage which will be also the voltage of CPU VDDIO.
9000 Series CPU IMC are specked for running at 5600 Mhz stock.

Check if you have bent CPU Socket Pins under bright light. Memory slots won't work properly if it is even slightly bent somewhere.
If it is bent somewhere, replace the Motherboard. Also check if entire Motherboard is slightly bent as that can also cause issues.
Carefully reseat CPU and make sure CPU Cooler is pressing evenly on CPU and is not too tight.
If it still doesn't work after that, consider replacing CPU as the IMC is probably of low enough silicon quality from factory it can't properly handle EXPO or memory channels properly.
 
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AMD needs to optimize AGESA to the point that CPUs will never need more than 1.2v on CPU VDDIO and CPU NB/Soc, and never exceeds 1.25v on VCore at stock. This will make EXPO lot safer and CPUs will last more than 10 years without degrading significantly, and CPUs will be able to boost and gain more performance due to lower VCore Voltage without needing to use Negative Curve Optimizer.
 
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