5 Things to Know When Mixing RAM Sticks

Match capacity, speed, and timings As long as the new stick has the same capacity, speed (MHz), and timings (CL), brand doesn’t matter much. The system will run both at the slower stick’s speed anyway.

Avoid mismatched voltage Different voltage ratings can cause instability. Most modern DDR4 and DDR5 sticks are 1.2V or 1.35V, but mixing different voltages often leads to crashes.

Watch out for rank differences Mixing single-rank and dual-rank DIMMs sometimes works, sometimes doesn’t. Picky motherboards may fail to boot or crash randomly.

Don’t buy a faster stick expecting an upgrade The system runs both sticks at the slower one’s speed. A faster stick paired with a slower one will just be throttled down.

Best practice is to buy a matched pair If you already have one stick, buy the exact same model from the same manufacturer. Failing that, match speed, timings, and voltage perfectly, and be ready to return it if it doesn’t work.