Question: are two case fans enough?
Answer: 2 case fans (1 intake in front, 1 exhaust at the back) show biggest improvements to cpu and gpu thermals. ... It depends on the hardware and layout of the case, but in general a single intake fan is enough for a general-use computer. For a low-end gaming PC, 1/1 is fine, 2/1 or 3/1 for higher-power hardware.