I searched more on the forums, and it seems there are quite a few people with this problem, with no response from Sandisk whatsoever. I opened a ticket to find out if there’s any development from Sandisk side on this issue.
Found a helpful postthat got me thinking about repartitioning and realigning partitions in the original configuration.
According to it, the original partition alignment is 32k, with the 1st cluster at 32k and formatted with 32k clusters.
All I managed using diskpart was to create an aligned partition at 32k and format it with 32k clusters, but didn’t find any way to align first cluster, which appears to be at 4k instead of the original 32k when I partition with diskpart.
After that I formatted to FAT32 with AOMEI Partition Wizard, since I couldn’t find anything else to let me format such a large partition with FAT32. HP USB format tool does format, but it repartitions too with other alignment, and I didn’t want that.
The result is that the flash is “almost” reset to the original performance, it writes at 190MBps (originally it wrote at 210MBps speeds). As soon as I reformat it to NTFS, the performance drops to an average of 2MBps, and severely oscillating, instead of writing continuously.
Still, I find it an immense PITA that there’s no way to format to NTFS without rendering it absolutely useless performance-wise, and I’m thinking of returning the drive, since there are other options that are close to that performance, less sensible to NTFS formatting and a lot more support.
If anyone has any idea, feel free to step in.
