Lexar confirms that CFexpress cards run hotter than SD cards in cameras – and says it's an industry-wide challenge

The Nikon Z6 and Nikon Z7 will receive more robust support for CFexpress cards.

Last November, Panasonic issued guidance regarding overheating issues on the Lumix S1II family of cameras. Along with a firmware fix, Panasonic reportedly advised creators to use SD cards rather than CFexpress as a way to manage heat issues. It was an unusual thing for a camera manufacturer to say in a briefing; essentially recommending a slower, older format over the newer, faster one that its own camera was designed to support.

The memory card industry, to my knowledge, didn't respond to this issue directly at the time. But recently, I had the opportunity to ask Lexar directly.