Check if your motherboard supports 12V RGB lighting. If not, you may need a compatible adapter.
Check if your motherboard supports 12V RGB lighting. If not, you may need a compatible adapter.
You might have affected that color channel. Usually there are small transistors or MOSFETs for each color—red, green, blue... one could be faulty or a tiny fuse may have blown from a short circuit. Replacing it would make a difference. It would be useful to know the motherboard model and to have a clear photo of the area around the RGB header in case others can't find close-up images online.
Well, I think it's probably one of those three transistors or MOSFETs in the top right spot on your photo, or near it in this shot from the Gigabyte site. These parts act like switches—when activated, the pin connects to ground, allowing current through the 12V pin to pass through the LED and back into the motherboard via one of the three pins. If the MOSFET is on, the pin stays grounded and the colored LEDs light up. By switching the chip on and off, the board adjusts the brightness of that color. If you see no color at all, it could mean the connection from the pin to the IC is broken, or the chip itself is faulty—no response whatsoever. When it fails, it usually stays on like a short circuit inside, so you'd always see full brightness green. If the chips have some code (usually 2-3 letters), you might be able to identify the exact model and possibly repair it at a repair shop. It might not be worth sending the board back for an RMA—your board is still functional except for this small problem, which doesn’t impact performance. But if you bring it in, they might offer a refurbished unit instead of replacing the whole thing.
I demonstrated the damaged component featuring the blue circle.