B450M Don't work RGB

The software is specifcally for the RGB controller chip, on the board itself.
Is your other RGB compatible with Polychrome RGB.
Is there a controller, between the boards RGB connector and the fans, this can be the culprit.
You could try to connect a fan directly to the header on the board, but be careful, Addressable RGB, uises 5 Volt (grey connector), the white RGB supplies 12 Volt, and will ruin the LED's.
If the fan works like should be expected, the cause is this controller, and you could try, using an RGB splitter cable.
What also can help, is to run the RGB firmware update.
The first time you start the RGB tool, it will detect tghe LED peripherals, once that is done, there should be also a firmware update, but you have to be patient, give it some time.
If this fails contact the manufacturer of the LED hardware, or use the support form
https://event.asrock.com/tsd.asp
When using gmail, check your spam folder for replies.
Also some of these RGB controllers, can be controlled by a button, and in some cases, you have to keep the button pressed, before it can respond to the onboard LED controller