The Ultra have terrible random IO compared to most other cards - just look at any benchmarks. It feels more like either really cheap memory, bad programming at the controller side or they're intentionally throttling to make the Extreme cards look better. If the base card was good they wouldn't have a market for the Extremes 🙂 Rick has said it's a controller issue on multiple occasions now.
Sequential write speeds are lower than the reads but technically way above what any dashcam should ever need at over 10MB/sec.
The 128GB MicroSD cards look pretty bad too in the benchmark scores so I think we're potentially going to hear of more problems as people use them.
I've got a good mix of cards here, 2x Sandisks, 3x Samsung and a Kingston and to be fair they've all been ok for me so far.
The Sandisks did throw a low speed warning on the 3H2F but works fine in the G90 so it would appear it can be worked around in firmware. Not sure if the Mini0803 uses similar code?
If the cam can't hammer down the cache to MicroSD fast enough it's going to cause carnage.
