Slow Samsung 960 Pro m.2 RAID 0 performance.

[Nikorasu95]

Hey everyone

I recently got 2 new 512GB Samsung 960 PRO M.2 Drives. I installed them on my new Maximus X Apex and installed windows on them (RAID 0).

Now, using a disk benchmark program, like CrystalDiskMark, I get around ~3200MB/s sequential reads and 3084MB/s for writes. A single 960 Pro is capable of 3500MB/s, why is it slower than that in a RAID 0 setup? Heck, why i'm not not getting twice the performance of a single drive?
Is it limited by the Motherboard's bandwidth? I have the PCIe lanes set to 3.0 for the Dimm.2 slot. I'm also using Intel's Rapid Storage which was the only way to make Windows 10 bootable on this platform. In device manager it shows Intel Raid 0 Volume.
I have the best motherboard for overclocking. Why the heck if my RAID 0 performance crap?


And, I noticed my transfer speeds are weird. Lets say i'm making a copy of a 11.5GB folder with mulitple files I'll get 5MB/s to 15MB/s. Why isn't it alot faster? I'm using RAID 0 for christ sake.
Stripe size 128Kb.

The rest of my specs is:
CPU: i7 8700K @ 5GHz
Motherboard: ASUS MAXIMUS X APEX
RAM: 16GB DDR4 @ 4133Mhz
GPU: GTX 1050 Ti
PSU: EVGA Super Nova 750G2
OS: Windows 10 Pro x64 16299.125
HDD: Western Digital Black 3TB
HDD: Western Digital Black 6TB

[Nikorasu95]

Also, there are people with better performance than me. Heck, some even have the Samsung Evo in RAID 0 and its faster than my 960 Pro in RAID.


And this one


This person has the 960Pro in RAID 0 and its faster than mine. What is going on here?

[Wolfdale]

Have you installed the Samsung NVMe driver? If you are not sure you can launch AS SSD benchmark (google it) and on the left corner it would either say "secnvme" or "storahci". You need to be using the "secnvme" driver.

[Nikorasu95]

RAID 0 Windows 10 bootable can only be done with Intel RST in the BIOS. In device manager it says Intel Raid 0 Volume, so installing the Samsung driver just gives the error "Samsung NVM Express Device is not connected. Connect the Device and try again"

[yj668]

That's the DMI 3.0 bus for you.
They're using actual PCIe links.

[davidzill]

Did you use the dimm.2 riser card for your ssd’s?

[Korth]

Your "weird transfer speeds" probably aren't abnormal.
You don't get striped performance benefits when simultaneously reading and writing data across a single RAID volume.
And there cannot be RAID performance benefits when moving data between M.2 SSD RAID and SATA HDD non-RAID.