Hello Chata,The 3pin connector is from the Digital RGB LED of the CPU water block.It only fits 3pin, 5V digital RGB slot on the motherboard. Sorry that there is no cable that can connect the 3PIN to 4 PIN RGB slot.But you can choose a Digital RGB controller (BPTA-DRGBMFC-V2 )to control the RGB, as the following link.https://shop.bitspower.com/index.php?route=product/product&path=4_5&product_id=7822