Question PC Build Issue – No Display, Self-Rebooting, Debug LEDs Cycling B760M

[Cursed Chico]

PC Build Issue – No Display, Self-Rebooting, Debug LEDs Cycling


Here’s my current build:

• PSU: MSI MPG A550BN ATX
• Motherboard: MSI PRO B760M-P DDR4
• CPU: Intel Core i5-13400F (2.5 GHz)
  → These three components are new.
• RAM: 32 GB Ballistix (2x16 GB)
• Storage: I have 2 SSDs but haven’t installed them yet.
• GPU: Sapphire (I forgot the exact model)
• Monitor: GamePower (confirmed working with my laptop)

I removed one RAM stick to test, but the issue persists.

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Problem:


After installing the parts:

1. On first boot, the system briefly shows a sequence of debug lights (white → red → black?) then automatically reboots.
2. On the second boot, only the white, yellow, and green debug LEDs come on — and they stay on.
3. There is no display output, either via HDMI or DisplayPort. The monitor stays in sleep mode.

I reset CMOS using a screwdriver on the JBAT1 pins as per the official MSI manual. I unplugged the power, shorted JBAT1 with the screwdriver for 10 seconds, then plugged back in and booted — but still no change.


I tried booting with and without a USB stick containing Ubuntu. When the USB is inserted, the final LED stays white, which according to the manual means “no VGA detected.”
When I remove the USB, the LED sequence changes slightly but still ends in green/white with no display.

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Other Notes:

• The PC was working earlier at the computer shop in "display mode."
• I'm wondering: could something have been damaged during transport?
• I’m using the cables that came with the PSU.
• Unfortunately, I don’t have access to another monitor to test easily.
• I tried both HDMI and DisplayPort, neither works.

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Questions:

• Why does the system reboot after the first power-on?
• Could the issue be the GPU, PSU, or motherboard?
• Is this a known problem with the MSI PRO B760M-P DDR4 and i5-13400F?

Any suggestions for what else to try?

photos:
https://ibb.co/FqYKv92J

Whats-App-Image-2025-05-05-at-11-54-20-AM hosted at ImgBB

Image Whats-App-Image-2025-05-05-at-11-54-20-AM hosted in ImgBB

ibb.co

https://ibb.co/FqYKv92J

Whats-App-Image-2025-05-05-at-11-54-20-AM hosted at ImgBB

Image Whats-App-Image-2025-05-05-at-11-54-20-AM hosted in ImgBB

ibb.co

 

[Lutfij]

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time. Since you swapped parts out, it's best you pass on a before and after of your specs list.

https://download-2.msi.com/archive/mnu_exe/mb/PROB760M-PDDR4.pdf
Page 39, green LED would indicate that you don't have a boot drive on the board.

 

[Cursed Chico]

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time. Since you swapped parts out, it's best you pass on a before and after of your specs list.

https://download-2.msi.com/archive/mnu_exe/mb/PROB760M-PDDR4.pdf
Page 39, green LED would indicate that you don't have a boot drive on the board.

Yes i dont have boot because i did not put any ssd. first i want to see bios screen. Now i cant see anything. All fans are spinning. 3 parts are new so 0 years old. cpu,psu, mb.

psu: MSI MPG A550BN ATX PC
motherboard: MSI PRO B760M-P DDR4
cpu: Intel Core i5-13400F 2.5 GHz
RAM: 32 GB Ballistix RAM (2x16GB)
Storage: 2 SSDs but not installed
GPU: (I forgot the model but sahppire.)
monitor:gamepower

i also took one ram out but same.

At computer shop, i could see it was working in display mode. So, can it be about monitor or i broke something while i was bringing to home? he could not i think also use from hdmi.

 

[Cursed Chico]

Update: I went again to pc shop. And again worked there!

I used my power cable so not about it. I guess 2 possibilities.

1- My display cable is broken.
2- At first setup, it works only via vga.

Because shop's monitor is vga. He uses vga to display, so it can give display. Wİthout ssd. I also put usb and could see ubuntu menu.

We could not test my display cable because he has vga . And my motherboard has vga but i think because of cpu, no integrated vga.

And there also hdmi did not work.

Before, in old system, hdmi was working with same cable. BUt not same system of course. it was amd before. But now i can use with that hdmi cable to laptop and it works.

What i can do is now to buy new display cable to see if really broken. If not-probably not-, i need vga monitor and vga to display changer.

I also read somewhere at first only via vga but i could not find it.

What do you think?