Fans are buzzing but the system remains unresponsive.
Fans are buzzing but the system remains unresponsive.
I press the power button on my PC and the fan's color changes rapidly, then begins spinning before stopping. This occurs multiple times and continues even when I keep holding the button. After a short pause and repeating the action, the same problem persists. Could this indicate a motherboard, power supply unit, or CPU fault? Please advise. System details: Windows 10 64 bit Z390-A PRO (BIOS 1.BO 8/10/2020 UEFI), Intel i7-9700K, 3.6GHz, 2x8GB DDR4 RAM at 2700MHz, NVIDIA GeForce RTX 3070, 1TB NVMe M.2 SSD (Gigabyte 750W 80+ gold), PSU 3000MHz.
Hello, welcome to the discussions. Is this your first PC setup? Have you attempted to reset the CMOS settings? When your device is powered down yet still connected, use a metal object such as the end of a screwdriver and connect these two terminals for 10 seconds. After that, power it back on to check if it functions properly.
Is this a freshly assembled unit? Page 36 of your motherboard guide indicates debugging lights are active—what do these indicate? (Pua caught me early!) These lights can signal issues like a misplaced CPU or memory connection, suggesting you might need to re-seat components. If it's a brand-new build, double-check all connections carefully and ensure everything is securely attached, avoiding any loose screws or improper grounding between the board and chassis.
I've been working on this setup for about 2-3 years without any problems until now. Recently, during a quick debug, the CPU and fans would flash before the system stopped completely. I haven't checked the CMOS yet but will let you know once I do. When using a screwdriver, it would either trigger the LEDs and fans twice or not at all. Now it just keeps repeating the flashing. I've uploaded a video for clearer guidance. I turned off the PSU after watching it and restarted; the system booted back in within 30 seconds. IMG_8558.MOV
More videos are available showing the current situation. Warning: flashing alert—sorry the fans are upset. You’ll notice the debug indicator and what occurs when it loops endlessly. When I press the pins, as @Yua mentioned during the event, the loop halts and the PC shuts down completely.
Your machine appears to be stuck in a power cycle. Do you have an extra PSU? If yes, swap it and observe any differences; if not, proceed with a basic test for the power source. Begin by removing all cables connected to your computer. Locate the main power connector on the motherboard and use the retaining clip as a guide, following the instructions in the diagram. Connect a paperclip or wire to pins labeled PS-on with Black/Ground markings. Position the connector so that pin 4, column 2 aligns with either the pin above or below it. After securing, power should activate, signaling proper function. With a multimeter, verify the pin voltages match the reference image. If not, the fan may spin continuously, which is typical when pins are shorted—this can also happen if the motherboard is damaged.
I performed the paperclip test and the PSU is working, with fans initially running before stopping. About an hour ago, after completing all tests, my PC booted into BIOS and was reset. It appears to be functioning properly now, though I’m concerned it might just be a temporary solution. Thank you so much for your assistance—it has been extremely valuable.
It's discouraging, but previous discussions might have contributed to reviving this situation.