Do tall RAM sticks and big air coolers cause clearance issues?

Yes. Most tower-style CPU coolers overhang the RAM slots, and tall heatspreaders (40–50mm) can physically block the fan or heatsink. Standard RAM is 30–33mm, and many big air coolers only clear up to 35–40mm on the first slot. Check your cooler’s official clearance spec and compare it to your RAM height. If you already own the cooler, options include low-profile RAM, moving the fan, or switching to an AIO liquid cooler.