CPU indicator illuminated, no output or screen visibility. Power cuts off after brief pause.
CPU indicator illuminated, no output or screen visibility. Power cuts off after brief pause.
After a few days of troubles, I decided to take everything out for easier repairs. This time I’m really concerned the CPU might be faulty. What should I do or which components should I replace first? My PC has been sitting around 4-5 years, and I moved it into a new case after six months of inactivity. Since I reassembled it, there have been some problems—first it would randomly shut down, then I played games for a day without heavy use. It also froze and restarted itself several times. After updating the BIOS with a USB from 2018 to 2023, I entered the updated menu but had another random shutdown. I moved the AIO slightly because that was the first boot issue I encountered. Now it barely powers on for a couple of seconds, and the CPU light stays lit. So far, I’ve removed the motherboard battery a few times, rearranged the RAM, tried without any RAM, and taken out the drives—only the M.2 SSD is left, and the OS runs. The CPU looks clean. What could be wrong? My specs are an i9-9900k, MSI 1070 Ti, AORUS DDR4 3200MHz, Gigabyte Z390, gaming X Windows 10. Any suggestions on what might be failing or next steps? If I need to replace the core, maybe upgrading to a 13th-gen chipset would help, but I really hope there are other fixes I can try right now. When I tried recording a short video to show how it runs for a few seconds, it didn’t turn on at all—just stopped after about 30 seconds. What part could be broken?
^ You also want to use the 2nd RAM slot since it should be the primary controller A slot that a lot of motherboards require to be populated. I would also recommend seeing if you can POST with only a single fan connected to the CPU FAN header, removing whatever it is that's plugged into that top left fan header. I've had these sorts of issues with a fan that was shorted, as an example. Worth considering an actual hardware failure of the motherboard or such otherwise, 5 years is a good run and you'd benefit a lot from getting 13th generation, even with the 980ti (assuming its not the issue).
The system lacks internal graphics and appears to struggle with activating the CPU light boot sequence, likely the first one.
I've been testing various combinations while it started up briefly, but now it won't boot at all—just the motherboard lights up. I'm not sure if I made any changes before this, and I'm worried something might be damaged. Hopefully, it's not the main board.
It's clear the 9900k is no longer a strong choice for gaming. I'd focus on swapping out the M.2 or RAM first, as those fit easily into newer systems with LGA 1700. Still a decent PC, but not recommended for gaming in 2023. The recent CPU generations from both Intel and AMD have been really impressive, so upgrading would be a smart move. Healthy competition really benefits users.
I've been checking possibilities for a 13th gen i7 and a compatible motherboard that can share the same RAM. If I don't locate a fix within a week, I'll need to order new components right away since it's not booting at all. I'm unsure what might be wrong.
You're in a tough spot with your system. At the lowest RAM settings—CPU plus a single stick of RAM, 24-pin and 8-pin connections—yet no signal appears after resetting CMOS or updating UEFI—it means something is seriously wrong. You're definitely in a bad situation.
I removed the screws for inspection and noticed earlier boot issues because the AIO was overly tight. I resolved it quickly, and it worked for a short time—1 to 2 days—before another unexpected shutdown. After updating the BIOS, it rebooted briefly but then entered a strange restart loop. Eventually, I adjusted the pump and RAM, but it kept rebooting repeatedly. Now it won’t boot at all, and I’m unsure if the core was damaged or if the motherboard failed. I’ve documented everything so I can test parts before ordering replacements.