Mixing RAM kits vs buying a matched kit: Matched kit is safer, mixing usually works but has risks

Mixing two identical 2x8GB kits usually works, but matched kits are guaranteed stable. The risk with mixing is instability from different timings or voltages, especially at high frequencies (3200MHz+ on DDR4). Intel boards are more forgiving than Ryzen. If building from scratch, buy the matched kit; if upgrading and willing to troubleshoot, mixing is fine.