true blue 2 :
Hey folks, sorry for the delayed response on this. After extensive email conversations with Gigabyte support, we came to the conclusion the Toshiba NVMe drives were malfunctioning. The drives (Toshiba THNSN5256GPU7) were on Gigabyte’s QVL, and Gigabyte support proved to me (with screenshots and detailed test notes) that they were in fact supported, and could be setup in RAID without a lot of fuss. Their final recommendation was that the drives were somehow malfunctioning and I should RMA them back to the vendor. The supplier who actually drop shipped them to me (Super Micro) initially resisted the RMA, but the vendor I actually ordered them from (BLT) fought diligently on my behalf and got the RMA pushed through. During all this, I purchased a set of Samsung MZVPV256HDGL SM951 NVMe drives and they worked fine from the moment I installed them. They cost a little more, and have slightly lower R/W specs, but they worked right out of the box and eliminated all the headaches I was having with the Toshiba drives.
Thanks to everyone who contributed. And BTW, for anyone that believes RAIDing these drives is a waste of time and/or has no significant advantages, my Crystal Diskmark tests are showing ~3200 MB/s read (which I believe is near the saturation point for the PCIe bus) and ~2500 MB/s write. Show me a consumer SSD drive of any type that will do that by itself (without RAID) and I’ll consider giving up my belief that RAIDing is the best way to go when you want maximum performance from your drives.
I'm also going to buy 2 x Samsung SM951 NVMe for my Z170X-UD5 mobo and want to use RAID0.
Would you be able to confirm 2 things for me please?
1) Are you able to boot OS from RAID0 in such configuration? How about multi-boot?
2) Gigabyte website states the following:
"With two PCIe Gen3 x4 M.2 connectors onboard, GIGABYTE brings to the user PCI-Express connectivity for SSD devices. Delivering up to 32 Gb/s data transfer speed per connector, the dual M.2 provides an ideal storage solution as it also supports RAID modes.
UP to 32Gbit/s + UP to 32Gbit's"
According to Samsung MZVPV256HDGL SM951 NVMe specification:
Sequential Read Up to 2,150MB/s Sequential Write Up to 1,260MB/s
I'm wondering why you are getting ~3200 MB/s read in RAID0 "only".
If M.2 slots are using two separate x4 PCIe lines, then you should be getting near 4300 MB/s in RAID0. Ok, maybe not exactly as RAID0 is never x2 speed of single drive but still...... I would expect a bit more than 3200MB/s.
I'm just wondering where is the limitation?
OK, all is clear now.
"The Z170 chipset, however, is limited by DMI 3.0 to about 3.4GB/s sequential performance for read and about 3GB/s for sequential writes."
So the thing advertised by Gigabyte is simply not true.
Read more:
http://www.tweaktown.com/articles/7553/samsung-950-pro-pcie-gen-3x4-nvme-ssd-raid-report/index.html