Bios settings for Samsung 960 EVO NVMe?

[-Lightmaster-]

I don't seem to get the maximum performance out of my Samsung SSD. It's rated at 3200MB/s read and 1900 MB/s write and the best benchmark I got using Samsung Magician is 3100 read and 1300 write. (similar result using CrystalDiskMark)
Something is seriously hampering my write speed but I can't figure out what it is.
What bios settings should I use? Any other hints and tips?
I have the latest firmware 2B7QCXE7

My system:
Z170 Gaming K3, bios version F22
Intel i5 6600k
Corsair 16 GB 2666 MHz
Samsung 960 EVO 250 GB
Seagate Firecuda 1 TB
Gigabyte 1060 3 GB

[autotech]

As long as you have it set to AHCI on the controller you have it set right. When a SSD advertises speed you don't always get that speed sometimes you get a slower speed. That is because when they post the advertised speed it is always at the maximum speed and not all run at that speed. 

[-Lightmaster-]

Thank you for your answer. I know I can't expect to get the advertised speed but there is just too much deviation. It seems to work just fine for other users as my speed is in the 10th percentile when using userbenchmark, meaning 90% of the users with the same SSD get better results. That's why I suspect the mobo.

[shadowsports]

Lightmaster,

All of what AutoTech has said regarding maximum vs. theoretical bandwidth is true.  Your speeds do sound to be very good.  Afraid I don't have anything definitive to add.  Have you tried disconnecting the FireCuda and running the benchmarks again?