Hello everyone! This is my first post and this motherboard is driving me crazy because everything looks so non-trivial that I don't know where to start investigating. During these days I believe I watched half of the YouTube videos trying to understand how to troubleshoot power cycles but at the same time, I'm confused because my motherboard doesn't always do that and sometimes completes the POST for a few seconds: the right amount of time to freeze, show glitches on the screen, and then reset itself.
Let me give you a bit more context to understand why and how we got here.
In the past few months, my mother was the owner of this PC: she used it mainly for six to seven hours a day doing RDP. Powered by an 80W picoPSU, i3 4130T, and two sticks of DDR3 1600 with Windows 10 and an SSD, it started behaving weirdly by crashing after a few hours of work and showing glitches. My mom solved the problem by turning the pc off and back on. Over the time, the crashes have become more frequent until today, where it's nearly impossible to even reach the bios as the motherboard 9 times over 10 enters in power cycles, and when a power cycle completes, it shows a message on the screen to enter BIOS or reset to factory defaults but no matter what I do, after pressing a button or waiting for a few more secs, the PC crashes and glitches are shown on the screen and everything become unresponsible: after a few seconds the motherboard restart itself and the cycle start happening over and over.
I was thinking about bad caps, so I bought an ESR tester, but everything looks good on the motherboard. I also measured vcore from the MOSFETs near the CPU and power is there. Also, the memory rails look well-powered (I don't remember the proper voltages but I can measure them over again if you need to). The power cycle only happens if I put a memory stick into the PC, if I don't put RAMs, the speaker starts beeping three times long, and after a minute, the motherboard restarts itself starting beeping over and over. I also tested the motherboard with a GTX 650 but it glitches the same as using the iGPU. I was thinking about VRAM, and that's why I tested the caps and the power stages near the memory, but as I watched many videos on YouTube, maybe the PCH or the Nuvoton chip could be the cause of my problems. The odd thing is it's not easily reproducible: sometimes the power cycle happens, and sometimes the glitches happen, so I honestly don't know how to start troubleshooting and what voltages/values I should measure to understand what's going on.
I also want to mention that after I disassembled the CPU for the first time, I noticed a pin on the socket that was slightly off its position: it was really difficult to detect because it looks fine if you look at the board from different perspectives but I assumed it's not the root cause because everything was working fine before disassembling for the first time. I also noticed a strange look on some of the pins of the socket: looks like they are less shiny than other pins in certain areas where I also spotted a strange glaze on the motherboard that looks like flux. I honestly don't know if the socket has been replaced before because this motherboard is secondhand and has been used by another guy before my mother did. But we're talking about three, four, or more years ago as I have owned this board since 2020.
I know basic electronics, I know how to use a tester, and I know how to replace components, I'm not so good with SMDs but I want to also master the ability to troubleshoot motherboards and PCBs, any kind of suggestion would be much appreciated, please just let me know where to start digging around I'll be right back to you with infos and measurements. Thanks!
Let me give you a bit more context to understand why and how we got here.
In the past few months, my mother was the owner of this PC: she used it mainly for six to seven hours a day doing RDP. Powered by an 80W picoPSU, i3 4130T, and two sticks of DDR3 1600 with Windows 10 and an SSD, it started behaving weirdly by crashing after a few hours of work and showing glitches. My mom solved the problem by turning the pc off and back on. Over the time, the crashes have become more frequent until today, where it's nearly impossible to even reach the bios as the motherboard 9 times over 10 enters in power cycles, and when a power cycle completes, it shows a message on the screen to enter BIOS or reset to factory defaults but no matter what I do, after pressing a button or waiting for a few more secs, the PC crashes and glitches are shown on the screen and everything become unresponsible: after a few seconds the motherboard restart itself and the cycle start happening over and over.
I was thinking about bad caps, so I bought an ESR tester, but everything looks good on the motherboard. I also measured vcore from the MOSFETs near the CPU and power is there. Also, the memory rails look well-powered (I don't remember the proper voltages but I can measure them over again if you need to). The power cycle only happens if I put a memory stick into the PC, if I don't put RAMs, the speaker starts beeping three times long, and after a minute, the motherboard restarts itself starting beeping over and over. I also tested the motherboard with a GTX 650 but it glitches the same as using the iGPU. I was thinking about VRAM, and that's why I tested the caps and the power stages near the memory, but as I watched many videos on YouTube, maybe the PCH or the Nuvoton chip could be the cause of my problems. The odd thing is it's not easily reproducible: sometimes the power cycle happens, and sometimes the glitches happen, so I honestly don't know how to start troubleshooting and what voltages/values I should measure to understand what's going on.
I also want to mention that after I disassembled the CPU for the first time, I noticed a pin on the socket that was slightly off its position: it was really difficult to detect because it looks fine if you look at the board from different perspectives but I assumed it's not the root cause because everything was working fine before disassembling for the first time. I also noticed a strange look on some of the pins of the socket: looks like they are less shiny than other pins in certain areas where I also spotted a strange glaze on the motherboard that looks like flux. I honestly don't know if the socket has been replaced before because this motherboard is secondhand and has been used by another guy before my mother did. But we're talking about three, four, or more years ago as I have owned this board since 2020.
I know basic electronics, I know how to use a tester, and I know how to replace components, I'm not so good with SMDs but I want to also master the ability to troubleshoot motherboards and PCBs, any kind of suggestion would be much appreciated, please just let me know where to start digging around I'll be right back to you with infos and measurements. Thanks!
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