How to Pick a CPU Cooler That Won't Bottleneck Your Chip
Picking a cooler by TDP, case airflow and CPU class so you do not silently throttle yourself.
The under-cooling trap
A 13700K with a stock-class cooler hits 100 °C and throttles in any sustained workload. Frames vanish, average FPS drops, 1% lows tank. The CPU is not the problem, the cooler is.
Sizing rules of thumb
| CPU class | Minimum cooler |
|---|---|
| i3 / Ryzen 3 | Decent 120 mm tower (e.g. Hyper 212) |
| i5 / Ryzen 5 (non-K) | 120 mm dual-tower or 240 mm AIO |
| i5-K / Ryzen 7 | 240 mm AIO or premium air (Peerless Assassin) |
| i7-K / Ryzen 9 (non-X3D) | 280 / 360 mm AIO |
| i9-K / Threadripper | 360 mm AIO + good airflow |
Air vs AIO
Air is quieter at idle, lasts forever, has no pump to die. Top-tier air coolers match 240 mm AIOs in real workloads.
AIO clears taller RAM, looks tidy, scales better with 13900K-class heat. Buy from a brand with a 5+ year warranty.
Don't forget case airflow
The best cooler in a sealed glass aquarium still bakes. Front intake, top + rear exhaust, mesh front. See thermal throttling for how to verify.
Quick test
Run Cinebench R23 for 10 minutes. If your CPU stays under 90 °C with clocks holding, you are fine. If it climbs to 100 °C and clocks fall, your cooler is the bottleneck.
Related reading
Run your own numbers
Open the free bottleneck calculator or estimate FPS with the FPS calculator.