Do I Need Top Ventilation for My New PC Build?

While I'm not sure you'll see a big improvement, adding a 140mm exhaust fan at the top could be a good idea. If you're looking for budget options, ThermalRight fans are solid, but Arctic Pros are really popular as well—just keep in mind they might be a bit loud unless you adjust the fan curves.

Are you actually having temperature problems, or are you just preemptively trying to solve a non-issue? If you're not experiencing high temps with your current setup, you might not need to worry about additional fans. But if you do want to ensure good airflow before your components arrive, you could consider a couple of top fans just to be safe.

It's generally better to have airflow going from the front to the back of your case. The idea that hot air naturally rises isn't entirely effective for cooling a PC. As long as you have a good exhaust fan in the back and some intake fans at the front, you should be good without needing more fans on top.

You can definitely add top fans if you want, but with three intake fans, that should be sufficient to keep your temperatures in check. If you start noticing higher temperatures with your components, then maybe consider adding more fans later, but for now, it should be fine.