Board no update, power switches on, fans spinning, CPU indicator red even after replacing the chip.
Board no update, power switches on, fans spinning, CPU indicator red even after replacing the chip.
I possess a vintage 1155 socket Asus Sabertooth Z77. I encountered a non-functioning machine with no idea why it stopped working. Initially, I suspected the issue was caused by excessive dust blocking the GPU heatsink and fans (the CPU heatsink wasn’t as severely affected). After checking, the board displayed a red CPU indicator and failed to show any video output. I assumed the CPU was dead (it ran at 3570k) so I purchased a Celeron 460 to test the system. After swapping in that CPU, the same problem persisted. The motherboard lights up with a green power indicator, the CPU fan spins up, and only the red CPU light activates. What do you believe this implies? Could the board still operate but have a faulty internal component triggering that red light? I doubt the seller would send me a completely dead Celeron 460, though it’s not impossible given its age. Essentially, I’m focused on identifying which parts are still working.
The brand and model of the board you're using vary significantly, affecting POST LEDs and code readouts.
If the CPU was overclocked, it might have been stressed too much and isn't responding. My motherboard behaves the same way when I push my CPU beyond its limits. Consider resetting the BIOS by adjusting and connecting the correct pins on the motherboard, then attempt to boot again. NOTE: I pushed it excessively as in overclocking too much.
Updated post, now running an ASUS Sabertooth Z77. Checked the manual—it didn’t include a troubleshooting guide for the index section. I’ve done a lot of overclocking, so I’m testing the second CPU to verify the 3570k is still functional. When I first tested the board, I cleared the CMOS to ensure it booted properly. After swapping the CPUs, I noticed it wouldn’t power on immediately from the power switch. Eventually, I cleared the CMOS again and the fans and lights activated. I resolved the issue by shorting the power switch pins.
Verify the CPU socket. Are there any bent or absent pins in the socket? Just to confirm, you purchased this setup in its original condition and have never experienced issues before, correct?
I verified the pins during the CPU swap and everything looks fine. The board itself is in solid shape too. I actually acquired it for free, and its past performance is unclear except that it stopped working somehow. Based on what I've seen, most parts fail and the whole unit becomes unusable, which is why it's often called a "broken computer." Usually only one component is faulty, even though other parts might have suffered. Initially I thought it was a dead CPU, but after swapping the CPUs, I suspect the issue might be with the board itself. I'm new to diagnosing dead boards and know they can be the hardest to figure out.
Some issues I've noticed suggest a possible fault with the power header on the board for the 8 pin EPS. You might fix it by using just a 4 pin connection. I'm checking if switching to a 4 pin resolves the problem.
Are you attempting to start it without the case? Yes, I’d do that. I’d use only essential parts to display an image. I’d test it with a known working GPU, sufficient RAM, and a functional PSU.