Connection to the CPU power cables isn't working.
Connection to the CPU power cables isn't working.
Hi, it's been a while since I kept my loop in check. I cleaned and rewired the water cooling system yesterday. Everything seemed normal until my computer shut down suddenly. I own a Z390 AORUS XTREME motherboard with a 9900k CPU. There are four 16GB RAM sticks installed. The CPU has its own CLC system, separate from the one I just cleaned and rewired for my EVGA FTW 3 3080. I used an EVGA GQ 1000 watt 80 gold PSU for testing. I ran some tests using a tool that clips onto the main power cable. When the PSU isn’t connected to anything, it still functions. If I connect peripherals, the pump works fine. The PSU powers on when connected to the main cable. With the GPU and SATA power plugged in, it makes a click but doesn’t turn on. The fan doesn’t spin when I connect the PSU. After a few minutes, it starts spinning again. Did something go wrong with the PSU, the CPU, the RAM, or the board? How should I troubleshoot this?
You're using a 24-pin ATX bridging plug? If it's connected, the ATX port isn't linked to the motherboard—meaning power isn't reaching it. The system won't start correctly, and the plug remains attached. This device is meant for testing fans, pumps, loops, etc. It shouldn't supply power to the CPU (8-pin) or connect to PCI-E cables for the graphics card, nor should it handle SATA power for SSDs or HDDs. It's not designed to switch on the system by shorting pins; instead, it triggers a safety cutoff. A *click* suggests a short circuit, overcurrent, or overvoltage alert. Verify if any component is being shorted to the chassis, case, or motherboard.
Thank you for your reply. I usually rely on the jumper in the manner you specified, but after my computer shut down I felt I could try further. Since you mention a possibility of shorts, I’ll thoroughly disassemble and reassemble the system to avoid any issues. I hope it resolves itself once I’m done tonight. I’ll share the results afterward.
I've taken apart the computer and simplified it to its core parts. The motherboard, CPU, RAM, and CPU AIO are all present. I found some moisture on the back plate near where the 8-pin CPU power cables attach. This might have occurred during disassembly, but it seems more likely it happened when I was assembling the board yesterday. After drying it and using a datavac blower, I’m hopeful there’s no lingering moisture. When connecting the ATX 24-pin to my PSU, the red light activates for the on-mobo power button. Pressing it makes the PSU fan spin, which is normal since the CPU isn’t powered yet. Plugging in the CPU power cables and turning it on produces a click. It’s unclear what else to fix, but I’m not sure the motherboard is beyond repair.
You don't require both 8-pin EPS cables. One 8-pin EPS can deliver up to 384W to the CPU; it's unrealistic for an i9-9900K to need close to 400W, let alone 700W+. Try connecting just one of the 8-pin EPS power ports. It might cause a short in one of the motherboard's 8-pin EPS sockets or a cable. Any moisture near the 8-pin EPS connection on the motherboard isn't a good sign. Could it mean a leak or liquid spillage?
Hi! Thanks for your feedback. I've connected the PSU to each socket separately using both cables, but nothing seems to be working. It's possible the moisture entered during your water loop maintenance. I hope it wasn't an issue, though—I'm just guessing. It's hard to tell since everything is below the tubes and radiator. I do have a CLC AIO radiator above those EPS sockets, but it hasn't leaked.