Generally poor performance is hardware based, ie MB config and set-up of SSD
MB Config Should be Sata III controller and set to AHCI
For SSD set up see:
https://www.partitionwizard.com/partitionmanager/how-to...
and https://www.auslogics.com/en/articles/ssd-tweaks-to-inc...
General Info:
Seq Performance: Not as Important as 4 K. Boot time is primarily a function of the 4K random reads (majority of files on OS drive are under 32K). Seq read/writes become important when working with LARGE files such as Video. Most SSDs preform about the same for Seq (That is you will not see much diff between Good and Excellent SSDs OUTSIDE of bench marks). Random read/writes can me much better in the Better SSDs and depends on the type of Cells...