Yeah, generally something high performance. Or sometimes something that has been miniaturized but still puts out a lot of heat that needs to be dissipated.

Example:
https://www.amazon.com/WD_BLACK-SN850-Consoles-Solid-Heatsink/dp/B0B4SWQ39Y

SN850X 7,300 MB/s - https://www.amazon.com/gp/product/B0B7CKZGN6/

SN850 7,000 MB/s - https://www.amazon.com/gp/product/B0B4SWQ39Y/

https://www.tomshardware.com/news/wd-black-sn850x-pcie-40-ps5-ssd-hits-retail-4tb-for-dollar820

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If we compare the SN850X to the previous SN850, we're looking at 4% higher sequential reads and 25% higher sequential writes. Random read and write speeds have gone up 20% and 53%, respectively.