Terrible write speeds on Sandisk 120gb plus ssd under Osx

Bought a sandisk 120gb plus to my mac mini (5,1) and i'm getting really poor write speeds from it under High sierra. (Max 90mb/s, tested with blackmagicdesigng's disk speed test) Reads are fine tho, (around 500mb/s) High Sierra: http://ift.tt/2Cd9OCV

So i thought i'd test it also under windows 10. It seems that the write speeds are a lot better there Windows10: http://ift.tt/2zPyU4H

*I've tried with trim off and on, but getting same results. *Ssd firmware is the latest. *Re-installed Os couple times, no change.

Can anyone help?

Submitted December 30, 2017 at 04:20PM by pertti123123 http://ift.tt/2Cd31cg