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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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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Other vendors are facing similar issues, Asus included. But on MSI side the bios are new and on beta so it may make things worse. Buy the RGB version mentioned, seems to work fine with everyone that tries.
 
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I am using it with the bios that came from the factory. I am using patriot viper xtreme 5 7600 mt/s ram, which is not on the qvl list. Also, this ram doesn't even have Expo. I set the times manually and have no problems. I'm very pleased so far
 
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Hello, i finish my build today and i got a 9800x3d with a x870 tomahawk and 2x16 vengeance cl30 6000 mhz corsair (CMK32GX5M2B6000Z30) and i also cant use expo, the system wont post and i get a6 error. Anyone changed the rams and solved the problem? its frustrating because i didnt want to send this rams back to waranty
 
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bruno.costa.1996.b155b02df said:
Hello, i finish my build today and i got a 9800x3d with a x870 tomahawk and 2x16 vengeance cl30 6000 mhz corsair (CMK32GX5M2B6000Z30) and i also cant use expo, the system wont post and i get a6 error. Anyone changed the rams and solved the problem? its frustrating because i didnt want to send this rams back to waranty
Click to expand...
As mentioned multiple times, changed to the RGB version and it works. Or you can just wait and hope for a bios fix.
 
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marcos.vidal.154a02d1 said:
As mentioned multiple times, changed to the RGB version and it works. Or you can just wait and hope for a bios fix.
Click to expand...
I would wait but the problem is, when are they gonna solve this problem? Im so mad about this right now, i invested so much money on this build and now that i cant waste any more money, this happens. I hope that the rma isnt that long for corsair
 
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"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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bruno.costa.1996.b155b02df said:
I would wait but the problem is, when are they gonna solve this problem? Im so mad about this right now, i invested so much money on this build and now that i cant waste any more money, this happens. I hope that the rma isnt that long for corsair
Click to expand...
I dont know, i dont see anyone from MSI clarifying anything about this, so... I sent back my memories to the shop I bought it from and purchased the RGB ones on amazon.
 
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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?"
Click to expand...
I use the same motherboard with a Ryzen 9 7900X, 32 GB Corsair, a Sapphire RX 6750XT and a Samsung 990 Pro as well as several SATA SSDs. THE BIOS is the latest version 7E51v1A1A.
The system runs stable, boots quickly (Win11 login appears after approx. 25-30 seconds.) No problems with LAN, Wifi or Bluetooth.
The only thing that doesn't work is the expo profile of the RAM. This is probably due to the RAM used by Corsair. According to CVL it should be CMK32GX5M2B6000Z30 Ver.5.43.01, unfortunately I have 5.43.13 and the Expo does not work at all (system starts, but hangs with an ‘Ab’ error).
 
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Kasmi said:
What is the current status of this motherboard? Should I completely avoid it?"
Click to expand...
It's perfectly stable (prime95, Karhu, 3DMark, gaming) in combination with my 9800X3D and 2x32GB Kingston Fury Beast 6000MT/s CL30 (KF560C30BBEK2-64).
EXPO Profile 1 works perfect.
I really like this board. The only thing I miss is a 'final' UEFI version.
 
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New ryzen master is out, you are supposed to be able to enable expo inside the system, has anyone with not compatible expo kits tried to enable expo once booted?
 
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Kytos said:
New ryzen master is out, you are supposed to be able to enable expo inside the system, has anyone with not compatible expo kits tried to enable expo once booted?
Click to expand...
I have tried to set the EXPO profile via the Ryzen Master (Version 2.14.3286). After a new boot, the system hangs with error ‘Ab’ and yellow RAM LED.
Even a cold boot had no effect. I had to perform a ClearCMOS and set the bios again.
 
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Welp, I also made the mistake of buying the CMK32GX5M2B6000Z30.
EXPO worked, optimized settings worked, but my games were crashing because of a GPU error and my network was losing speed or dying out completely.
Although... I tried using the first "Memory Try It!" option which is the same rating as the RAM and things have been working flawlessly for two days. Does that mean I'm good or should I still worry? Replacing in my case is a bit of a hassle, but not impossible.
 
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New Bios 7E51v1A1F(Beta version):
- AGESA PI-1.2.02b.
- Improved overclocking capability for high-density DDR5 memory module.

Looks like they did something 👀
 
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