Check your motherboard model, not the slot shape.

Look up the exact motherboard model on the manufacturer’s website or a spec database like PCPartPicker. That’s the only reliable way.

DDR4 and DDR5 slots look almost identical — same length, same number of pins, but the notch is in a slightly different spot. It’s easy to misjudge, and forcing the wrong stick is a bad time. Your CPU generation also matters because the memory controller is on the CPU. For example, Intel 12th gen and later support both, but the motherboard you pair it with locks you into one.

If you don’t have the board’s box or manual, check the model in Windows (msinfo32 or wmic baseboard get product,manufacturer) or look at the board itself for a printed model number. Then Google that plus “memory support” or “specs.”

Don’t trust the price or the seller’s filter alone. Double-check.