A 12V JRGB header is the standard 4-pin config: | | | | A 5V ARGB header is a 3pin config: | | _ | So it's super obvious that it doesn't fit. I think the 5V headers let you do more specific light addressing, like rotating light patterns and all that, which it seems I indeed WOULD need a controller for. I'm not looking to get that complicated.. JRGB is for non addressable lighting, meaning you can only set one colour to all the LEDs connected to it. You cannot convert it to anything else, and you should not plug anything ARGB into it. If you need an ARGB header and your motherboard doesn't have it, you will need to look for something else.
Note: The JRGB port and JRAINBOW port provide different voltages; if the 5V LED light strip is connected to the JRGB port, the LED light strip will get damaged. There are detailed descriptions of the pin definitions and the connection methods of the light strip and fans in the user manual.. The JRGB are 12V headers which are the ones you want to use. The JRAINBOW are 5V headers which are used for addressable RGB 3 pin devices Thanks! Question, Can I use the sys_fan port on my mobo to power my fans? I am planning to transfer my old ARGB fans to the front of my case so I am wondering if that is the purpose of the port.