Is DDR4 RAM compatible in a DDR3 RAM slot?

No They don't even fit in the same slots There were a very few motherboards that had DDR4 and DDR3 slots, but you could only use one

CPU: Ryzen 5 3600 · Motherboard: A320M 2 Ram Slots · Ram: 16GB DDR4 3200mhz · CPU Cooler: RGB CPU Cooler · SSDNvme: 128GB SSD · Hard Drive: 500GB · Power Supply: E-

ddr4 vs ddr5 slot The position of the notch on DDR4 memory modules is also different from DDR3 modules This prevents accidental insertion of the wrong type of memory because

ddr4 sodimm slot DDR4 DDR4 3200 DDR4 2933 DDR4 2667 DDR4 2666 DDR4 2400 DDR4 2133 DDR3 DDR3 2400 1 Slot 1x288pin Others 12x288pin 6x240pin line_back