PC fails to boot, persistent red CPU indicator on motherboard following overclocking (recent build).
PC fails to boot, persistent red CPU indicator on motherboard following overclocking (recent build).
Hey everyone, I've finished my latest setup after a week of work. Everything was running smoothly—no overheating, everything stayed cool and stable. Today I decided to push it further by overclocking my new I9 9900K CPU to 5.0GHz using a YouTube tutorial. I set the vcore to 1.350v as instructed. After saving and exiting, the PC didn’t boot again. The fans and cooler spun for about ten seconds before the system restarted, but the CPU debug LED stayed solid red. I tried resetting the BIOS with a CMOS jumper and removing the battery, but nothing worked. Am I probably damaged my CPU? Since I couldn’t test the new settings, it seems unlikely. Could my PSU be the issue? I’ve had this power supply for over four years from my previous build. I didn’t replace it thinking a 650W would suffice for an RTX 2080 Ti and the I9 9900K. I just ordered a new 850W unit, which is on its way. In the meantime, how can I check if my motherboard or CPU is still functional? Thanks for your help!
Keep it off temporarily and press the power button firmly. Try again later. Oddly enough, this has worked before.
RAM installation likely didn’t succeed. You must reset CMOS properly. Yet there are instances where, after turning off power using the power button following a RAM timing issue, the BIOS becomes completely damaged instead of just the power switch. This issue affects models like the Aorus Pro, Ultra and Wifi, because these devices lack an internal mechanism to alternate between main and backup BIOSes (as noted in a Buildzoid video for RAM testing on the Aorus Master).
Disconnect the AC power source from the wall or cable. Use a screwdriver to connect the CMOS jumper to short for 30 seconds. Reconnect the AC power supply. The system should now boot normally after several rapid start-up cycles (typically two quick 1-second on-off bursts, then a 30-second cycle, followed by a POST).
If this doesn’t work, follow these steps:
1) Turn off using the power switch, then press and hold power+reset buttons until the system shuts down.
2) Power on. The BIOS should switch to the alternate version and boot.
3) If unsuccessful, try these alternatives:
- Disconnect AC, remove RAM and CPU from the socket, connect power cable, turn on without RAM. This may corrupt BIOS but can sometimes be fixed if the BIOS is unrecoverable.
- Disconnect AC, extract RAM and CPU, plug in power, turn on without CPU. Then insert RAM, power off, reapply thermal paste (have spare paste ready), restart. This always works if CPU or BIOS are intact.
These actions force the BIOS to fully reinitialize and reset its memory, bypassing CMOS issues. If all else fails, the motherboard may be severely damaged, indicating a corrupted BIOS. The CPU itself is unlikely to be the problem.
Thanks for your reply. It seems my bios might be damaged. I’m considering sending both the CPU and motherboard back to Newegg just in case. I’m hoping the request will be approved since I ordered the parts only a week ago. Also, do you know how strict Newegg is about returns or replacements? I’ve noticed a few screws missing in my motherboard case, but I’m sure it shouldn’t cause any issues.
Attempt to launch with just a single RAM stick in place—could trigger the BIOS to detect a hardware change. I’m suggesting this only because I faced a comparable problem when overclocking my 5820k, where a BIOS reset and battery replacement failed. Using just one stick instead of four seemed to reactivate the BIOS. Not sure if it’ll work, but it’s worth a try before ordering a replacement.