Rare problem on MSI Z77A-G41 board when powering up

[diegito11]

Good afternoon colleagues, I have a problem with a desktop board MSI Z77A-G41 MS-7758 ver.3.1 that I have changed the super IO because it did not start but now I have another case that I can not find out, it turns out that it turns on and I enter bios but just bridging the green wire with ground, from the switch the fan only makes a couple of turns but it does not stop.
Turning on with the bridge gives me access to bios but when I turn it off it turns on but it does not give a video signal, if I reset bios on the bridge that has the board, when I turn it on again it gives me a bios signal again.
I have reprogrammed several bios from the official page but I still have the same symptoms and I don't know what it can be, sometimes it has given me 3 short beeps that I think is a memory failure that I have also changed several even new ones without any problem.
I have boardview but 2.0 and my board is 3.1.

[dicky96]

Re: Rare problem on MSI board when powering up

This is a bit of a guess but I think you may have a problem with the PCH as this is mainly responsible for correctly handling the reset signals and starting the ATX PSU. I have a similar fault but on a totally different type of board and chipset.

In my case changing the SIO made no difference. I can get the board to start by bridging the green wire on the 24 pin ATX connector but it seems to boot up in an indeterminate state (sometimes i get it to beep as there is no RAM inserted)

I don't know if it will help any but here is what is happening with mine. I now suspect PCH but I don't have any board view or schematics for my board so it is very difficult to diagnose.

https://www.youtube.com/watch?v=MdDFaUiQI-4

[piernov]

Re: Rare problem on MSI board when powering up

The SIO is what triggers the PSU PS_ON# signal, after receiving SLP_S3# from the PCH. The SIO also monitors the power button, and sends PWRBTN# to the PCH as a response.

[dicky96]

Re: Rare problem on MSI board when powering up

Hi piernov
As both the OP and myself changed the SIO (OK different chip sets but very similar problem) then I thought the PCH would be the next most likely culprit - though I don't have a schematic/board view for my board so it is a bit of a guess

[piernov]

Re: Rare problem on MSI board when powering up

Different boards, different set of symptoms, different problems so (usually) different solution. Troubleshooting process is the same though.

[diegito11]

Re: Rare problem on MSI board when powering up

I have thought about the PCH because when it turns on well with the bridge that I make, the pch tends to get too hot I think, but I wanted to ask to see if someone had happened something similar to it.

[dicky96]

Re: Rare problem on MSI Z77A-G41 board when powering up

Does the PCH get hot when you just have 5V Standby?

[piernov]

Re: Rare problem on MSI Z77A-G41 board when powering up

PCH getting hot when turned on and working is normal.

[Schorsch87]

Re: Rare problem on MSI Z77A-G41 board when powering up

Does the PCH get hot when you just have 5V Standby?

This behaviour leads to a dead pch. I had the same problem with an x58 board from gigabyte.

[diegito11]

Re: Rare problem on MSI board when powering up

The SIO is what triggers the PSU PS_ON# signal, after receiving SLP_S3# from the PCH. The SIO also monitors the power button, and sends PWRBTN# to the PCH as a response.

Actually I have no signal from slp s3 # in the super IO so the pch is dead, the same thing happens to me with another Z77 motherboard from asrock, I mean to throw the board away.

[piernov]

Re: Rare problem on MSI Z77A-G41 board when powering up

There are a lot of things going on before SLP_S3# comes up.

[diegito11]

Re: Rare problem on MSI Z77A-G41 board when powering up

There are a lot of things going on before SLP_S3# comes up.

hello piernov, can you guide me where to look? or research,? I am not a professional but I am little by little analyzing it and studying what I can.