Excellent work man! 240mhz obtained 80.8MB/s write speed on 5D3 ...
Thanks!
... do you think reducing the clock speed to 160mhz would increase the longevity of the hardware? or is it simply there for backwards compatibility with older cards?
Correct, some SD cards aren't fast enough and doesn't work with high frequencies like 192 MHz and 240 MHz. That's one reason why 160 MHz is there.
I don't know if lower clock speeds help with "increasing the longevity of the hardware".
There is one little quirk I've managed to reproduce. "Free memory" in debug menu throws ERR70 every time
That's not related to SD overclocking, but to RAW video. When RAW video is activated (mlv_lite) it allocate all available memory, and once you higlight (or maybe click?) on "Free memory", an ML function which analysis free memory would run and would conflict somehow with RAW video, because of RAW video allocated all memory. I had this problem before.