Nepton 120XL AIO is powered on but not circulating water.
Nepton 120XL AIO is powered on but not circulating water.
I performed a standard dust removal and refreshed the thermal paste on my Cooler Master Nepton 120XL AIO, positioned in the middle-top of my case (the waterblock beneath the tubing entry on the radiator, the CPU on the left of the radiator, which is the rear of the case). The pump/waterblock was previously connected to the CPU_fan header, and the fans in the standard SYS_fan headers. After cleaning, I restarted the PC and observed temperatures rising to over 80°C during startup. There was no water flow in the tubes, no noises or vibrations detected. I attempted to connect the waterblock/pump header to SYS_fan headers and also disconnected all fans from their respective headers, running the waterblock solely through the CPU header—still no improvement. I verified the waterblock speed in BIOS; the CPU_header was showing around 2600rpm, set to Normal for my Gigabyte B85-HD3 rev 2.1. It briefly dropped to zero for a split second, possibly due to the BIOS adjusting fan speeds to compensate. The logo on the waterblock lit up, and the fans spun from the SYS_fan headers. It appeared to recognize itself and power on. I reset the CMOS and updated the BIOS to the latest release. After removal, I reapplied thermal paste, reinstalled the waterblock, and rotated the radiator carefully (to avoid air pockets). I also connected a standard fan to the CPU_fan header, which functioned correctly, including adjusting speeds in BIOS. I managed to lower temperatures to roughly 30–40°C by reapplying paste and securing the waterblock tighter, but they quickly spiked back to about 60°C during activity. I noticed occasional brief bubbles, but the water didn’t move at all when booting or running. It seems the issue might be related to air pockets in the system, though the water isn’t flowing despite fan activity. I’m uncertain what’s causing it unless a pump fails and still registers as operational. Thank you for your assistance! Specs: Windows 10 Enterprise LTSC 64-bit, Intel Core i7 4790 @ 3.60GHz, NVIDIA GeForce GTX 1060 3GB, 16.0GB DDR3 @ 798MHz, Cooler Master Nepton 120XL AIO, Gigabyte B85-HD3.
The optimal action at this moment is likely just a few bubbles forming, possibly due to a “vapor lock” or reduced flow within the block.
It's time to review the bios settings. No matter where you connected your pump, it needs to be configured in bios either at full speed or adjusted according to the pump's requirements. Pumps are built to operate only at full speed, which is currently my understanding—still relatively new in the cooling technology scene.