My custom-built PC worked normally until this morning, but now it will not POST. The motherboard shows a steady orange DRAM indicator. The fans and GPU lighting turn on, but there is no display output and the keyboard and mouse do not power up.
The system has a Ryzen 7 9700X, Radeon 9070 XT, Asus TUF Gaming B650-Plus WiFi motherboard, and Crucial Pro 32GB DDR5-6400 CL38 memory. I reseated both RAM sticks, tested each stick individually in different slots, unplugged the power supply, and held the power button for about 30 seconds. Nothing changed.
Since the computer was working fine yesterday and was built about a year and a half ago, what is the most likely cause? Should I focus on testing the RAM, motherboard, or power supply, and is there anything else I should try first?
3 Answers
The power supply is still worth considering. A failing PSU can provide enough power for fans and lighting while not delivering stable power for the CPU, memory, or motherboard to complete POST. Testing with a known-good PSU would be the quickest way to rule that out.
If possible, boot a USB memory diagnostic such as MemTest. That can help confirm whether one of the sticks is faulty, although a system that cannot POST may not be able to run the test. Also try clearing CMOS and leaving the system powered on for several minutes afterward, since DDR5 memory training can sometimes take a while.
A component can fail even after working normally for a long time. Based on the DRAM light and the troubleshooting already attempted, the motherboard or memory are the main suspects. RAM often has a long warranty, so testing it and checking RMA coverage would be a good next step.
I was wondering about that because the fans and GPU lighting still turn on. I will try a known-good power supply if the memory checks do not reveal anything.