Slow random 4k Q1T1 writes on my SSDs in CrystalDiskMark

[Dave3000]

I have 2 PCs and one of them, the NUC, has a 250 GB Samsung 970 EVO Plus (NVMe) and a 120 GB Samsung 750 EVO (SATA). The other PC (main PC) has a 2 TB Samsung 850 EVO (SATA). My 970 EVO Plus is getting around 87-96 MB/s on the random 4k Q1T1 write test in CDM. My 750 EVO is getting around 67 MB/s on that same write test on the NUC. On my main PC, my 850 EVO Plus is getting around 87 MB/s on that write test. I used to get around 114 MB/s with my 850 EVO SSD on that same write test in CDM. I also use to get around 130 MB/s on the same write test with my 750 EVO on my NUC. My 970 EVO Plus, I purchased about a week ago. One odd thing that I discovered in CDM was that the 3rd time I ran the benchmark the 4k Q1T1 write test on my 970 EVO Plus dropped from 140 MB/s to 96 MB/s and continues to range between 87-96 MB/s on that test until I reinstalled Windows and CDM then it goes back to 140 MB/s for the first three times I run it then the speed in that write test drops back to 87-96 MB/s again. In the AnvilBenchmark, I get around 125 MB/s on the random 4k write test on my 970 EVO Plus. Also why is the random 4k Q1T1 write test in CDM much slower than it was last year in Windows 10 for my SSD's, even after doing a manual trim through Samsung Magician? Is it related to the Intel security patches (Spectre and Meltdown) for Windows 10?

 

[fire400]

do you have access to older season win10 builds?

it could be that the new win10 seasons may be hampering the environment for testing.
would it be possible to run other benchmark software other than CDM?
Can you post results with Samsung Magician's benchmark tool?