POST lights stop at VGA or BOOT every now and then.

Troubleshooting Intermittent POST Failures: VGA and Boot Hangs on a Custom Desktop Build

Building a custom PC can be an exciting project, but it also comes with its share of challenges. Recently, I experienced an intermittent issue where my system would fail to POST (Power-On Self-Test), often freezing on messages like “VGA” or “Boot.” In this article, I’ll share my experience, diagnostic steps, and potential solutions to help others facing similar problems.

System Overview

My desktop build includes the following components:

Motherboard: MSI 650S
Graphics Card: PowerColor Red Devil Radeon RX 9070 XT
Power Supply: MAG A750GL (750W, 80 Plus Gold)
Processor: AMD Ryzen 5 7600X
RAM: 32GB T-Force DDR5
Storage: 1TB NVMe SSD in the upper M.2 slot, 2TB NVMe SSD in the lower slot
Cooling: Thermalright Peerless Assassin CPU cooler
Case Fans: 8 meticulously installed fans

Initial Success and Emerging Issues

Initially, the system operated flawlessly for several months. However, over the past two months, I started experiencing POST failures approximately once a week, sometimes up to three times. The system would hang on messages indicating issues with VGA (graphics card detection) or the boot process. The frustrating part was that a simple power cycle—turning the system off and on—resolved the issue immediately, allowing normal operation until the next occurrence.

Troubleshooting Steps and Observations

Hardware Seating and Cabling: I verified that the graphics card was properly seated and that all power and data cables were secure. Physical connections appeared solid, ruling out loose cables as a cause.
System Stability: During normal operation, the system exhibited no crashes or glitches outside the POST failures. No sudden bugs or crashes suggested a stable environment once past POST.
Component Interactions: No hardware changes or driver updates coincided with the beginning of the issue, indicating it might be related to hardware initialization rather than software conflicts.
Power Supply Confidence: Given the 750W PSU with ample headroom, I questioned whether power delivery issues could be involved but found no immediate signs of instability during operation.

Potential Causes and Next Steps

Intermittent POST issues on modern systems can be caused by various factors: