Help with PC that doesn’t boot unless motherboard shows numbers that are NOT 00

Understanding Boot Issues Related to Motherboard Display Codes: A Case Study

Introduction

Encountering hardware initialization problems can be a frustrating experience for PC builders and users. One common indicator of system status during startup is the motherboard’s display codes, which provide valuable clues about the hardware’s state. In this article, we analyze a specific issue where a custom-built PC fails to boot unless the motherboard displays a code other than “00,” accompanied by alert lights. We will explore potential causes, troubleshooting steps, and preventive measures to resolve this problem effectively.

Case Overview

The user reports that their PC will only boot successfully when the motherboard’s display code shows a value other than “00.” The motherboard, an MSI MEG X670E ACE, demonstrates red and yellow LEDs when displaying “00,” indicating an error or standby state. The issue has persisted for almost a year, gradually worsening over time, despite prior BIOS updates and system adjustments.

System Specifications

CPU: AMD Ryzen 7 7800X3D
Motherboard: MSI MEG X670E ACE
RAM: 64GB DDR5-6000 (2x 32GB G.Skill modules)
Graphics Card: Galax GeForce RTX 4090
Storage and other components are assumed standard

Symptoms and Observations

The motherboard displays “00” during power-on, accompanied by red and yellow lights.
The system fails to boot into the operating system in this state.
Turning the system off and on multiple times sometimes results in a successful boot with a different display code.
When the system does boot successfully, the display code indicates normal operation.
Attempts to access BIOS are unsuccessful because the system boots directly into Windows without displaying the BIOS menu.
The user has undervolted the CPU and enabled XMP profiles, suspecting these settings might influence boot stability.

Potential Causes

Memory Initialization Issues

The display code “00” can sometimes suggest memory or POST (Power-On Self-Test) failures. Although the system runs stable once booted, persistent display of “00” might indicate instability during POST.