RGB madness, I may have gone overboard

Ok, is the first step to fighting addiction admitting you have a problem?

I bought a combined 300 watts of RGB and white LED strips for my case and monitor.

180 watts of digital RGB at 60 watts, 144 diodes per meter; total 180 watts if I use all 3 meters

120 watts of analog 5000k 95 cri white, 40 watts/meter at full power (expensive it turns out) as “bias lighting” behind my 43" monitor

The digital RGB is 5v. That presents a problem. My Corsair RM850x power supply only provides roughly 120 watts at 5v, and who knows how much is being used already. I’m thinking I could use a three 60 watt step-down converters. One for each meter of cable, running them off the 12 volt rail?

I need to do some measuring, cutting and soldering to find out how much of the 5v strips I’ll need.

The analog white is a lot easier. I have an external 180 watt 12v supply for, should be all good there.

Thoughts, ideas, comments?

120W in LEDs is enough to light an entire house. No idea why you would want to RGB your house, but okay.


I would suggest you get a dedicated 5V and 12V power supply. I have had good experience with TDK-Lambda.

Then you take the address signal (I guess is what you mean by “digital RGB”) and couple it through an optocoupler to prevent back feeding unwanted voltage to your motherboard.


When I understood you correctly, you have:

  • 120W 10A@12V of white LEDs
  • 180W 36A@5V of RGB LEDs
    The second one beeing significant current, you will have to feed the strip on multiple “bus points” in order to prevent melting of the strip. I would even suggest having a slow blow 38A fuse after the PSU just in case.

Watts must be based on a different standard in China?

I used three meters to go around the back of my 43" monitor. At 12 volts the white led strip is drawing roughly 15 watts. Quite a departure from the advertised 40 watts/meter.

To maximize current balance, I’m feeding the string at two points roughly equidistant from each other, and the entire string is wired as a loop.

Not sure if I’ll get to the RGB this weekend, not looking like it.

Oh, you must be new to Chinesium stuff.

Chinese watt are roughly 2 to 4x as much as regular watt (this is a joke).
One example:

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