Xiaomi has put the REDMI K90 Max through a live gaming heat test, and the headline result is simple: the Redmi K90 Max cooling setup stayed cooler than two unnamed rivals. In a 4-hour MOBA run at 144fps with maximum graphics, the phone reportedly hit a peak surface temperature of 36.7°C, versus 42.8°C and 39.0°C for the other devices. That is the kind of gap gamers notice fast, even if the demo was clearly staged to make Xiaomi look good.
What Xiaomi is claiming about the fan
Lei Jun said the phone uses a ”large fan” and is tuned to improve airflow efficiency. Earlier reports point to a fan around 18.1mm in diameter, about 6% bigger than typical setups, with claimed airflow of around 0.42 CFM and up to 40% better utilization. Those are encouraging numbers on paper, but fan cooling in phones has a habit of looking better in controlled demos than in a warm room after an hour of actual gaming.
That caveat matters because Xiaomi did not disclose the ambient temperature, the exact test rig, or the competing phones. Without that, the demo is more directional than definitive. Still, a 6.1°C advantage over one rival and a 2.3°C lead over the other is a decent sign that Xiaomi has engineered something more substantial than a gimmick.
Redmi K90 Max design and durability details
The K90 Max shown in the demo came in a ”Space Silver” finish with a metal frame and slim bezels. The fan opening is built into the design, so this is not a subtle phone; it wants you to notice the cooling hardware. That is sensible in a segment where thermal performance is becoming a selling point, not just a spec-sheet footnote.
Xiaomi also says the phone carries IP66, IP68, and IP69 ratings, which suggests the cooling system is sealed well enough to survive proper dust and water protection claims. That is the tricky part for any fan-equipped phone: moving air and keeping the device weather-resistant do not naturally get along. If Xiaomi has pulled that off at scale, other brands will have to answer, especially in gaming phones where cooling usually means thicker bodies and louder compromises.
The real test will be outside Xiaomi’s demo
Leaked details also suggest the fan should stay relatively quiet under load, which would be a welcome change from the tiny turbine noise some gaming phones produce. If that holds, the K90 Max could land in an awkwardly good spot: aggressive cooling without the usual whine, and without turning the back of the phone into a hand warmer.
The next question is whether Xiaomi can repeat these results in independent testing. Fan-based phone cooling has been promised before, but consistency is the hard part, and the market has already seen plenty of slick thermal demos that looked less impressive once reviewers got the device. If the K90 Max really keeps its surface temperature in the high 30s during sustained gaming, competitors may need more than a bigger vapor chamber to catch up.