Air cooler vs AIO liquid cooler — which is better?
High-end air coolers (Noctua NH-D15, be quiet! Dark Rock) match 240mm AIOs in performance, are cheaper, and never leak. AIO liquid coolers (240/280/360mm) handle high-TDP CPUs, look cleaner, and free up space around the socket. For most builds, a good air cooler is the value choice; AIOs suit hot CPUs (i9/Ryzen 9) and aesthetic builds.
What size AIO do I need?
240mm handles most mid-range CPUs (Ryzen 7, Core i5/i7). 280mm and 360mm are for high-TDP chips (Core i9, Ryzen 9) and overclocking. Larger radiators dissipate more heat at lower fan speeds, meaning quieter operation. Check your case's radiator support before buying.
Stock coolers (AMD Wraith, Intel Laminar) are adequate for non-overclocked mid-range CPUs. Upgrade if you have a high-TDP CPU (i7/i9, Ryzen 7/9), plan to overclock, or want quieter operation. A better cooler lowers temperatures and fan noise, and can improve sustained boost clocks.