Lighting node pro killed my computer...?

Slightly hyperbolic title.

I built a new rig a few weeks ago using a corsair 570x crystal case, with its included 3 (sp i believe?) rgb fans.

As my build included a 1920x threadripper, and my old rig had issues with cooling and airflow, I decided to grab some rear/top fans, deciding on a HD120 rgb fan for the exhaust and 2 HD140mm rgb's for the roof, and then realising I had nothing but the stock controller to alter the colours I purchased a 3pack of the LL120's more or less just because it came with a lighting node pro.

Prior to the ll120's being installed my computer had been up and running for several weeks, but last night when I attempted to install the ll120's and the LNP, the computer failed to post.

It didn't just fail to post, it seemed to be utterly dead. My motherboard is an asus x399a, and the normal twinkling LED lights would not light up, the fans would not spin, no post screen etc. Even the Q-code display wouldn't turn on. The only sign of life was an orange light in the bottom right corner above the cases front powerswitch pin.

After pulling all the components out, grabbing an old power unit and finding that no help, checking all the power cables were in and all the ram and graphics card were properly seated, I was at a loss for what it could be, when I accidentally nudged the cable of the new lighting node pro I'd just installed.

For an instant my mechanical keyboard's LED's lit up, as did the mobo's, before winking back out. Upon removing the LNP all together the computer posted normally. I turned it back off and plugged the LNP back in, and the computer was back to showing no signs of life, although when I moved the wires that connect the LNP to a sata power connection, the mobo / peripheral's LED's would flicker back on every now and then.

I will use my other power supply and try to determine if its an issue with the psu's sata cable, although something tells me (given the jiggling of cables going into the LNP) that its more likely to be a fault on that end. Anyone have any insight into what's going on? It seems strange to me that a usb2 / peripheral piece of hardware could shut down the entire computer.

What this sounds like to me is short circuit detection kicking in.

I've had this happen when using the wrong cables with the power supply - using, in fact, a modular SATA power cable that wasn't wired for the power supply that I had it hooked to.

Now ... I'm not saying that's what you did ... but I don't know. If the LNP had a short in it (due to some kind of issue), then it could possibly kick off SCP.

Thanks for the response. My psu is a fully modular cooler master v1000.

I was using the one of the sata cables that came with it, however I had needed to add an extra 3set of sata cable (as in the cable has 3 sata ports coming off it), i believe I plugged both the fan hub and the LNP into it. After work I will try using either a different sata cable or my old power supply and see if using all those sata cables works.

I should also note, not sure whether relevant or not but when I was done and plugging everything back in to check if it would start, I did notice the power cable crackling a bit as i plugged it in, but thats not the most unusual thing in the world so I didn't think too much ofi t.

A power cable crackling is quite unusual. I wouldn't see this as a good sign.

And if you used SATA cables that didn't ship with the PSU, they may not have the correct pinouts, even if they fit in the connector on the PSU.

The sata cables were the modular ones that came in the pouch of cables with the cooler master v1000.

I'll isolate with a separate power supply and see if that solves my problem. Perhaps that one modular sata cable is faulty.