I'm building a system with a Radeon 9070 XT and a Ryzen 7 7800X3D. I found a Kingston FURY 32GB DDR5-6000 stick for €180, while 32GB kits made of two 16GB modules cost around €400–€500. Would using a single 32GB module cause noticeable performance problems, or would it be reasonable to start with one stick and add another later?
3 Answers
A single 32GB stick will run in single-channel mode, so it can reduce performance in some CPU-limited games and applications. The impact varies, but it’s generally better to use two matched modules when possible. Since two of those individual 32GB sticks would cost about €360, buying two may actually give you 64GB for less than the overpriced 2x16GB kits.
If you only need 32GB right now and the price difference is really that large, one stick will work. The 7800X3D’s large 3D V-Cache can reduce the effect of slower memory access in some games, so the loss may not be dramatic. Still, performance can vary by game, and adding a second module later is the better upgrade path.
I’d buy two of the €180 32GB modules if they’re the same model and timings. That gives you 64GB and dual-channel operation for around €360. Just remember that two separately purchased sticks aren’t guaranteed to be as well matched as a factory-tested kit, so enable EXPO only if the system remains stable; otherwise, reduce the memory speed slightly.

That makes sense. I was mainly comparing total capacity and hadn’t considered that two of the single sticks could be cheaper than the smaller kit.