Last week at this time, after the child's computer went to sleep and was awakened, it directly displayed a black screen. Then it restarted and scanned the hard drive before entering the system. After a few minutes, it black screened and froze. Upon restarting, the power light was on, but the hard drive was not reading or being recognized. There was no alarm, and it couldn't be shut down. It could only be turned off by cutting the power. When powered on, it would start up by itself. This happened twice, and I didn't dare to power it on again. I disassembled it and removed the memory. After reinstalling it, the problem persisted. I also reinstalled the hard drive cable, but there was no effect. Then I removed the memory and changed the slot, but it still didn't work. The initial judgment was that it could be a hard drive or boot issue; the worst-case scenario would be a problem with the BIOS, as there was no BIOS information displayed when powered on, and it remained black. It could also be a power supply issue.
The next day, I found some spare parts: one memory stick, one hard drive, and one power supply. After replacing the memory, it started to beep. Five short beeps, beep beep. Most likely a memory issue, but the old memory didn't beep. Strange. I replaced it with a hard drive I previously used for RAID 0. Plugging it in still showed the same issue, indicating it wasn't a hard drive problem. Then I replaced the memory again. This time, when powering on, the motherboard fault light was blinking, and it was quite noticeable as an ambient light. I noticed the CPU power supply connector was quite loose, so I thought about directly replacing the power supply. I didn't remove the old power supply; I just unplugged the motherboard power, hard drive, and CPU power connectors. I connected another power supply's connectors. It still beeped. Both memory sticks were beeping. I wiped the original memory stick and plugged it back in. It had a good effect. It passed the self-check and entered the system.
Upon entering the system, it prompted me that the configuration file was missing. I didn't pay much attention, thinking it would probably be fine after another restart. Then I shut it down to test whether the power supply had issues. I replaced it with the old power supply, but it still black screened. The power supply was faulty. I then removed the old power supply and replaced it with another working old power supply. Upon powering on, it lit up again. After entering the system, it still prompted a configuration file issue.
In the evening, I wanted to try to fix it. There were many methods online; the system repair and recovery mode took over an hour but did not fix it. A command scan also did not repair it. Since the child's computer had few installed programs and minimal custom configuration, I decided to reinstall the system directly. Then for a while, I installed Steam, Chrome, and Minecraft. This time, I installed a newer LTSC version that came with Edge. I didn't install the motherboard's built-in network card driver, and everything was normal until I restarted the computer; then it couldn't connect to the internet. I then installed the motherboard's built-in network card driver to restore it.
Then the child used another low-spec laptop to occasionally watch videos, until this morning when he wanted to play Terraria. I had it installed, so I let him use the repaired desktop. After twenty minutes of powering on, it suddenly black screened again, but restarting was normal. After playing for more than an hour, when I asked him to write an English test, the computer black screened again. I checked the information and found that the causes of black screens almost involved all hardware. Alright, I’ll continue to observe. It might be a power supply issue. The new power supply is also expensive; it might be better to sell the CPU, memory, and motherboard. I’ll look for other second-hand complete computers. I’ll keep observing. I’ll run a diagnostic later when I have time.
Additionally, I found out today that there were no cloud saves for Terraria on Steam; I had to click to sync to the cloud. The child played from the beginning because of this. I’ll check for saves tonight. The achievements are still there, but the saves are gone.
The configuration is i3 9100, 8GB memory, 512GB mechanical hard drive, Gigabyte motherboard.