AMD B550 AMD AM4 Socket for AMD Ryzen 5000 Series / 4000 G-Series / 3000 Series Desktop Processors AMD Ryzen 5000 Series / 3000 Series Desktop Processors: 4866(O.C)/ 4600(O.C)/ 4400(O.C)/ 4266(O.C)/ 4133(O.C)/ 4000(O.C)/ 3866(O.C)/ 3600(O.C)/ 3466(O.C.)/ 3200/ 3000/ 2800/ 2666/ 2400/ 2133 MHz, Un-buffered Memory AMD Ryzen 4000 G-Series Desktop Processors: DDR4 5100(O.C)/ 4800(O.C.)/ 4600(O.C)/ 4400(O.C)/ 4266(O.C.)/ 4133(O.C.)/ 4000(O.C.)/ 3866(O.C.)/ 3600(O.C.)/ 3466(O.C.)/ 3200/ 3000/ 2800/ 2666/ 2400/ 2133 MHz Un-buffered Memory