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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Kasmi said:
"I am planning to buy the X870 Tomahawk or Pro motherboard to pair with the 9900X. I compared it with other models first and decided on this one. However, I later stumbled upon a YouTube comments where a user mentioned stability issues with this motherboard. What is the current status of this motherboard? Should I completely avoid it?"
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Yes you should completely avoid it! I purchased this mobo and I regret it deeply, BIOS full of errors, cant set ram to 6000 MTs. They update bios for 9800X3D and no update for 7800x3D. awefull! Go buy ASUS
 
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Just as an example, I'm using MAG X870 TOMAHAWK + 9800X3D + G.Skill Trident Z5 Neo RGB 64GB (2 x 32GB) F5-6000J3040G32GX2-TZ5NR.
Ram running at EXPO, with a little overclock to 6200, using 1:1.
CPU using -30 undervolt + 100Mhz overclock, very basic.
1734235525272.png


It's running great for weeks using 7E51v1A1A.
I would try to flash 7E51v1A1A, clear the CMOS and start from there.

I'm planning to upgrade only after the first non-beta version.
 
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Wow, as the OP, thought I'd come back for a look. Seems like a load of other people bought the same memory kit - Corsair cmk64gx5m2b6000z30 - like I did with same EXPO issue and different CPUs - how unlikely is it to be the IMC for all the different CPUs and more likely to be BIOS related? I just dont know. What I do know is I decided not to the touch the BIOS settings after getting it to run at a fairly lousy 5600 @ 40-40-40-77 on BIOS A16. Dont have the luxury of being able to spend time messing about with settings and need a stable system to do my daily job, at least its been stable but expected far better for the price paid. Will be super careful in future with mobo + RAM combos - once bitten, twice shy.
 
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pixelthefro1249029c said:
Having similar Issues with my setup, 9800X3D, MSI MAG Tomahawk X870 and 64Gb Corsair Vengeance CMK64GX5M2B6000Z30 CL30 6000 sticks.

have tried everything that's been listed to get the board to accept them, even tried with a single stick but the A6 error still occurs. I dropped back to the A16 Beta bios and things did improve with the boot cycle, the older bios boots faster and does memory training with each attempted change to memory speed however anything over 4800 will give the A6 fault. (Even 5600 causes this A6 fault)

At this point I'm just going to buy some G.Skill Trident Neo F5-6000J3040G32GX2-TZ5NR CL30 6000 sticks that are on the QVL list and hope the board accepts them, if not then the board is going in the trash and Ill go buy an ASUS board instead. The Sticks work fine at 6000 in a friends Intel board and the CPU is also working fine in an ASUS board with my Corsair sticks so neither part is faulty. I suspect its either a BIOS issue or the board itself is not compatible with these Corsair sticks or perhaps its the memory ICs since other CL30 6000 sticks are also causing the same A6 issue for others.

One thing to note is the older A16 bios will happily let me run the Corsair sticks at CL26-32-32-70 at 4800 with zero faults, might even be able to tweak the timings lower but right now that's what its happily running at.

Im regretting buying MSI, should have stayed away after all the issues I had with my 3080Ti Suprim X and the lack of Vbios updates for UEFI problems its got.
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Did you get the G.Skill RAM and was it the 64GB kit (2x32GB)?
 
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Does anyone have a 64GB memory kit (2x32GB) working with the X870 Tomahawk? Specifically, memory rated at 6000Mhz or above using EXPO with no issues or tinkering other than enabling EXPO? If you have, please let me know the model number with link. thanks.
 
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derekfoster1971262029b said:
Does anyone have a 64GB memory kit (2x32GB) working with the X870 Tomahawk? Specifically, memory rated at 6000Mhz or above using EXPO with no issues or tinkering other than enabling EXPO? If you have, please let me know the model number with link. thanks.
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Yes. I have F5-6000J3040G32GX2-TZ5NR. Working great so far using EXPO. Bios ver: 7E51v1A1A
 
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So when I enable AMD Expo, keyboard and mouse go dead. Monitor says no signal. Ram goes back to default RGB colour. And the PC just hangs not booting. I have to remove the cmos to fix it. I'm using a 7800x3d, msi b650 mortar, g.skill cl30 6000hz ddr5 4 x 16GB 32-GX2-TZ5NR. Bios version E7D76AMS.AHO Build date 07/25/2024. Cpu Speed running at 4.20ghz. Ddr speed 3600Mhz. Like what is going on 🙃
 
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Just writing to say that have the same problem using Corsair Vengeance 2x16GB (CMK32GX5M2B6000Z30) with EXPO. I have to reset CMOS to have my PC work again. I'm using a 9800X3D.
Please fix this. These Ram's are really good value and I see that are a lot of people first choose when making next machines and don't know about the problem.
 
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derekfoster1971262029b said:
Does anyone have a 64GB memory kit (2x32GB) working with the X870 Tomahawk? Specifically, memory rated at 6000Mhz or above using EXPO with no issues or tinkering other than enabling EXPO? If you have, please let me know the model number with link. thanks.
Click to expand...

I replaced the ram with Kingston FURY Beast 6000MHz 2x32GB (KF560C30BBEK2-64) and it now works with EXPO at the rated speed using 9800x3D and x870 Tomahawk.
 
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I also had the same problem with the Corsair CMK64GX5M2B6000Z30.
Installed the newest bios and also tried to set the specs manually. Nothing worked.

So i decided to change the ram. I replace them with Kingston FURY Beast 64GB, DDR5-6000, CL30-36-36, KF560C30BBEK2-64.
They are in the compatiblity list of the mainboard and also have nice timings.
 
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derekfoster1971262029b said:
Did you get the G.Skill RAM and was it the 64GB kit (2x32GB)?
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Yup got the 64Gb Gskill Neo kit and it works flawlessly at 6000Mt/s (SKU: F5-6000J3040G32GX2-TZ5NR)

Hoping that a future bios update lets the Corsair sticks work too, perhaps if and when it happens Ill be able to run 128Gb, even if its at 4800 or 5600 it'll be good.

I suspect that 4 sticks might be a bit much for the 9800X3D IMC but Ill give it a shot once the Corsair sticks are verified working.
 
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derekfoster1971262029b said:
Sadly, I am passed the point for returning for a full refund as felt I could wait it out for a new BIOS to resolve it, I am not sure that will be the case now. Just need to wait and see.
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If you set the ram timings manually, won't it work? My rams are not expo-capable and they are not on the qvl list. I bought it knowingly. I have never used expo. I always set it manually. Stabil
 
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