SD card Write Speed

I was catching up on my reading and saw this over on CR:

https://www.cameramemoryspeed.com/ca...best-sd-cards/


A nice ranking of SD card write speed with the EOS-R and shows that the write speed on the EOS-R is a significant improvement over, say, the Canon 5DIV:

https://www.cameramemoryspeed.com/ca...rd-speed-test/

Quick example, on the same Lexar 2000x UHS II 32 GB card, the EOS-R was clocked at 179 MB/sec vs 79 MB/sec on the 5DIV.

Both of those seem to be the upper limit for each camera as the R seemed maxed out around 180 MB/sec and the 5DIV around 80 MB/sec for the SD card and ~112 MB/sec for the CF card. So, the R is getting quite fast.

What interests me is that uncompressed 4K video at 30 fps needs ~250 MB/sec. Hence, the compression. Another point, the Nikon Z7 maxed out around 245 MB/sec with the XQD card, and the Sony A9 (no A7RIII data) maxed out at 152 MB/sec.