The PC requires two presses of the power button to start it when several USB devices are connected.
The PC requires two presses of the power button to start it when several USB devices are connected.
I’ve been facing an unusual power problem with my custom-built PC and wanted to check if others have encountered something comparable or offered guidance before considering a PSU swap.
On a cold boot, the machine powers up for roughly half a second before cutting off instantly. If I quickly press the power button again, it boots normally and functions properly. The odd part is that this only occurs when more than three USB devices are connected; removing a few allows the initial start-up to proceed without issues. It drops power after the first press, which I verified by setting “AC Power Restore” in BIOS to keep activating the power-on switch until it actually turns on. Previously, it was configured to Power Off.
The same pattern repeats when trying to wake the PC from sleep mode—except it’s even more sensitive. Even with just three USB devices connected, the system shuts down immediately upon waking, unlike a full shutdown or regular startup. This behavior is consistent with my current setup: AMD Ryzen 9 9950X, DeepCool 360mm AIO, ASUS ROG STRIX B650E-F GAMING WiFi (AM5), 64GB Corsair Vengeance DDR5 (2x32GB, 6400MHz), Kingston KC3000 4TB NVMe, Gigabyte RTX 4090 Gaming OC, FSP Hydro G Pro 1200W PSU (ATX 3.0, PCIe 5.0, 80 Plus Gold), and Corsair 5000D Airflow case.
This issue has been ongoing since about a year ago. Initially, it seemed linked to my table’s RGB USB connector; removing it resolved the cold-start double-boot problem. However, even after repositioning and taking it out, the sleep-related glitch remains. I haven’t been relying on sleep mode at that stage, but I’m exploring Wake by LAN features for potential use.
I’ve inspected all cables, updated BIOS and drivers, applied BIOS ErP settings, optimized defaults, disabled wake functions for USB/network devices, and performed multiple system diagnostics. Temperatures and voltages appear normal. I also tested running the PC on a single RAM stick and removing the GPU, suspecting excessive power draw, but found no improvement.
Currently, I’m trying to determine whether this is caused by a PSU fault, USB power delivery issues, motherboard hardware problems, or an unusual behavior in sleep states with the AM5 platform. Would anyone have similar experiences? Is there any indication that this particular FSP power supply is affected? I’d appreciate a proper diagnosis before proceeding with a return to manufacturer (RMA), especially since I work from home and can’t be without my machine.
In general, after a cold start, the system will turn on for roughly half a second before shutting down instantly. If I press the power button again shortly after, it restarts normally and functions properly.
JayzTwoCents shared this in a video where the board briefly powers up and charges its capacitors. On the second attempt, it opens the OS GUI. Since this wasn’t discussed earlier, does your system automatically start without pressing the power button on the front panel?
It usually starts with a lot of USB devices connected, and every time it goes into sleep mode. When you refer to “lots of USBs,” could you clarify which ports on the motherboard and the case are connected?
The ASUS ROG STRIX B650E-F GAMING WiFi (AM5) uses an updated BIOS.
For reference, the FSP Hydro G Pro 1200W PSU is an ATX 3.0, PCIe 5.0, 80 Plus Gold unit.
This problem has been ongoing since I assembled the PC about a year ago. Is this related to a power supply issue?
It might help to borrow or find a well-built 1.5KW PSU from someone else and test it. Purchasing parts for troubleshooting can drain your budget, so using a donor system is often more practical. Given that the issue worsens with USB devices, it could be either a short circuit from a USB device or a problem the motherboard has with managing those devices.
It does not turn on without pressing the power button, and it seems the button must be pressed twice quickly. My setup includes a headphone (CORSAIR HS80) on the front panel, a keyboard (HyperX alloy) and a mouse (Logitech G502) in the back ports. When all three are connected, the system boots normally but fails to wake from sleep. After connecting the USB that powers the table’s RGB lights to the back ports, the cold boot still requires two presses. The same happens when using the USB for an external speaker. I’ve checked which USB ports trigger wake-up, and it only responds with the keyboard connected—no other input wakes it. Even with just the mouse, it doesn’t activate without pressing twice, which is unusual.
I’m currently running BIOS version v3265. Over time, I’ve kept my system updated, but the problem remains unchanged. The power supply unit is a year old. Initially, I had to return my motherboard, processor, and AIO cooler because they were defective. I recall that with the previous motherboard model, this issue persisted, so I suspect it might still be related to the new one. I bought the necessary components in bulk from Canada Computers. Given that many parts were faulty, it’s possible the PSU could be the culprit. However, the fact that it has operated without issues for a year—except for the power button problem—makes me uncertain.
I’m unable to borrow a PSU to test since I don’t know anyone who owns one.
Fortunately, the maker sent me to the seller where I purchased the PSU, who provided an immediate swap for a better one. I received the Super Flower Leadex VII 1300W, and with this updated unit the problem has been fixed.