MSI 550a pro work only with RAM in A1 A2 Slot

[lucafava815c202ee]

Hello everyone, the motherboard only boots with the ram in A2 with a single bank or in A1 and A2 if there are two banks. If I put 4 4gb ram banks the pc does not boot and the dram debug light turns on if xamp is disabled or the cpu debug light turns on if xamp is enabled.

My configuration is as follows:
Mobo: MSI 550a pro
CPU: Ryzen 5 3600x with cooler arctic freezer esport
Ram: kit 4x8gb gskill 3200mhz
psu: Corsair 650w
vga: radeon 5500xt 8gb
Disks: 1 M2 pci-ex 4.0, 2 sdd 2tb wd blue.

I am sure that the ram is working because the banks all work in slots A1 or A2. I updated the bios to the latest version 7C96v28 and tried to reset, I tried to see if the heatsink screws were too tight.

I believe at this point that the problem is the cpu but I would like to be sure. can I do some other tests?

Thanks for you support.

 

[fatedust]

I believe at this point that the problem is the cpu but I would like to be sure. can I do some other tests?

Yes this sounds like CPU is faulty since system cannot boot when RAM in channel B. That points to CPU problem.
Can you check CPU pins and CPU cooler mounting pressure? Ensure that the pressure is even, an uneven mounting pressure might cause the same problem like you described.

 

[lucafava815c202ee]

Good morning fatedust thanks for the reply.
For the pressure of the cooler I also tried to start the pc with the cooler only resting on the cpu without tightening the screws but it did not start anyway. With the automatic oc of the ram the debug led stays on dram while with the oc of the ram in the car the debug led on the cpu stays on.

 

[fatedust]

Good morning fatedust thanks for the reply.
For the pressure of the cooler I also tried to start the pc with the cooler only resting on the cpu without tightening the screws but it did not start anyway. With the automatic oc of the ram the debug led stays on dram while with the oc of the ram in the car the debug led on the cpu stays on.

Do you have another working CPU to try? Better to choose a AMD 3000 series CPU so that you don't need to worry about the BIOS version support, since they're compatible out of the box.
But if you want to try an AMD 5000 series CPU, you have to make sure the BIOS is supported:
https://www.msi.com/Motherboard/B550-A-PRO/support#cpu

 

[lucafava815c202ee]

Unfortunately I do not have another processor to do the test but it is certainly the cpu because thinking that the problem was the motherboard I had done the RMA of the board and I have the same problem. The cpu pins are all in place and the cpu fits perfectly into the socket. To check the pressure of the heatsink I tried to turn on the PC with the heatsink only supported without screws and the problem remained. The bios is updated to the latest version and supports 3xxx series and 5xxx series. If there are no other tests to do I will buy another cpu. Thanks for the help

 

[citay]

Yes, looks more like the CPU then. These parts make up the memory system: The CPU's integrated memory controller (IMC), the mainboard and its BIOS, and the RAM itself.
So with the board replaced, the BIOS updated to the latest version (and such a fault wouldn't be caused by the BIOS), the RAM probably being ok, that leaves just the CPU to look at.
But why buy a new CPU yourself, can't you RMA the CPU like you did the board?

psu: Corsair 650w

What Corsair is that? Corsair had several dozen 650W models over the years.

 

[lucafava815c202ee]

Hello I already had the cpu but I had to change the motherboard because the other one had problems. As a psu I have the CX650M. At home I also had a CX550M and I have already tried this too but nothing has changed. Come on I'll look to buy a new cpu. Thanks for your support.

 

[lucafava815c202ee]

Hello, I bought a new processor, ryzen 5 5600 without x. The problem now is that the motherboard does not turn on (fans, LEDs, etc.) if the new or old cpu is inserted. If, on the other hand, I turn on the pc without cpu, the motherboard turns on! I tried to flash the bios again but it doesn't start. the power cables are inserted correctly I don't know what happened.

 

[citay]

I would try a completely different PSU now. Corsair CX-M is a low-end model and i don't know if the PSU can be considered being conclusively tested yet, if you tried with another CX-M PSU.
Sometimes people test with an old PSU they have lying around, this is not really enough. Ideal is a different - known good and not too old - PSU, or a new PSU. See my Guide: How to find a good PSU.
Because right now you're on your second motherboard (or did they just try to fix your first one?) and you have two CPUs to test with. So i would start back at the foundation now: The PSU.

 

[lucafava815c202ee]

Thanks for your reply, tonight if I can I will try to reassemble the corsair 550w just to do a test that worked on this pc and I used until a month ago. The problem arose from when I tried to reassemble the old cpu with its original heatsink to do a test. From that moment the motherboard has no longer received power with the cpu inserted. Yesterday the new cpu arrived and it gives the same problem. I also removed the cpu and flashed the bios with the usb key but nothing has changed.

 

[citay]

One thing i just noticed, what board do you actually have? Because you said in your original post:

I updated the bios to the latest version 7C96v28

7C96 would be https://www.msi.com/Motherboard/A520M-A-PRO/support
But there was no v28 version for it.

The board from the thread title is 7C56, https://www.msi.com/Motherboard/B550-A-PRO/support
Again, no v28 BIOS version.

And if your BIOS was already updated, plus it happened with the old and the new BIOS, then the BIOS can't have much to do with it.

Which CPU coolers did you use, Arctic Freezer 33 eSports and something else?

 

[lucafava815c202ee]

hello i tried to change power supply but the problem persists. I also checked the bios that I had downloaded and it is correct, I was wrong to write the version. unfortunately if I try to flash it with the cpu inserted, the flash fails.
at this point i think with the various tests i have done i have but ruined the motherboard.
As cooler i’m using only Arctic Freezer 33 eSports with 1 fan.

 

[citay]

So which BIOS is installed now to your knowledge?

What's the other cooler? Since you wrote:

The problem arose from when I tried to reassemble the old cpu with its original heatsink to do a test.

 

[lucafava815c202ee]

So which BIOS is installed now to your knowledge?

What's the other cooler? Since you wrote:

currently the motherboard has version 7C56. in the previous post I must have been wrong in the rush.
I tried to mount the stock cooler of the ryzen 5 3600x.

 

[citay]

7C56 is your board model. The BIOS version is after that. Example: 7C56vAA

 

[lucafava815c202ee]

The version is the 7C56vAA relised on 2022-05-26.

 

[citay]

Ok. What was the other PSU you tested it with now?

 

[lucafava815c202ee]

I tried the corsair cx550m which is definitely working because it is mounted on another pc. Unfortunately I have no way to try another one.
however the situation is always the same, without the cpu the pc starts up.

 

[citay]

I would still try to source a different PSU. Otherwise the logical move would be to try the CPUs in a different board...

About the board, is this the second motherboard now, or did they just try to fix your first one?

 

[lucafava815c202ee]

Hello, I don't know if I'll be able to test another psu or the new cpu on another system because I don't know anyone who has it. However, the current motherboard had come as a replacement for the first motherboard. Following the steps of the problems I tested: 2 different cpu, two power supplies, 4 ram banks .. Before the test with the stock heatsink of the old 3600x cpu (to verify that you have not applied too much pressure with the screws of the arctic freezer) at least the pc was booting with the ram in A1 and A2 now nothing more. Is it possible that during the assembly there was a micro electric discharge that damaged the cpu socket? And above all why if I start the pc without a cpu it turns on? Then if I try to flash the bios without cpu the procedure is successful but with the cpu inserted no. That's what I don't understand. Another thing that does not help the speaker makes no sound and no LED lights up.