Monstieur
With the newer BIOS versions, if you enable the "CPU Attached RAID" option in the UEFI and set the bifurcation to non-VROC, you can now create RAID arrays using the RST software in Windows instead of VROC. Previously RST was limited to chipset lanes. Both VROC and RST are just software RAID. VROC has a slightly better abstraction layer which hides the individual drives when the driver is not installed, but with RST the individual drives are visible without the driver. I don't believe there is any extra offloading done by VROC compared to RST - they're both done in the driver.
https://www.intel.com/con...upport_on_X299_FAQ.pdf

Monstieur

kram36
I was doing that over a year ago using none Intel NVMe drives. The problem that still exits, you must use Intel NVMe drives for a bootable Raid.

RST RAID has been bootable using non-Intel drives for 15 years or so. It's the same regardless of whether you use SATA or PCIe drives. Both chipset and CPU PCIe lines can be used to create bootable arrays with RST.
 
The problem could be the RST EFI modules in your BIOS. I manually upgraded the EFI modules to the latest 18.x version using the UBU tool at Win-RAID. IIRC the latest EVGA BIOS contains 17.x. Earlier BIOS versions shipped with 16.x which could not even create Optane Memory accelerated SATA drives though that was an advertised feature of the board.

Monstieur

JK_DC
I am having no luck with the Dark and NVME raid. I have cpu attached storage on, the slot with the hyper m2 set to non-vroc and pcie raid turned on. The IRSTe software refuses to install as it says the platform is not supported. I can install RST and it doesn't see the drives at all to allow me to raid them as a data drive although I can see them in windows and disk management.
 
I also have an AsRock that I tested the hyper m2 card on. I set it to enterprise in the bios and bifurcated it and set the slot to vroc aic and it works flawlessly as a data drive. IRSTe installed both sata and vmd driverrs.
 
The problem with the Dark is there is no device for the raid driver. I don't know if the enterprise switch in the AsRock bios exposes the nvme vmd device or not. There is no such option on the Dark. I am running the 1.28 BIOS on the Dark so it should work. If I set the slot to VROC on the Dark it refuses to POST.
 
I am souring on EVGA motherboards after purchasing the Dark. The CMOS battery was dead when I got it, SLI doesn't work and now I can't get nvme raid to work. I ordered a intel vroc key and some intel drives to see if it will make it work. Maybe it will expose the device id for the vmd raid controller after I install it. We'll see. Otherwise I will swap it with an ASUS board, which will probably work more smoothly.

Let me clear things up as I've tested all combinations extensively.
 
RST RAID with CPU Attached RAID enabled works only with PE6, PU1, (maybe PU2), PM1, and PM2, when using CPU lanes for these slots. You have to use the RST v18 driver and the Intel Optane Memory and Storage Management application. EVGA needs to release a BIOS update that supports all slots as other manufacturers support all CPU PCIe slots.
 
RST RAID with CPU Attached RAID disabled works only with PE6 and PM2, when using PCH lanes for these slots. You have to use the RST v18 driver and the Intel Optane Memory and Storage Management application. There is no reason to use this mode as it's bottlenecked by the chipset's DMI PCIe 3.0 x4 connection.
 
Bifurcation (PCIe slots set to non-VROC) works for PE1, PE2, PE3, PE4, and PE6, when using CPU lanes for these slots. No driver is required, but the RST v18 generic driver will work for NVMe drives. You have to use software RAID in Windows such as Storage Spaces.
 
VROC RAID works for PE1, PE2, PE3, PE4, PE6, PU1, PU2, PM1, and PM2, when using CPU lanes for these slots. You have to use the VROC v7 or v8 driver and the Intel Virtual RAID on CPU application. You can create a bootable RAID0 array in the UEFI or Windows application with Intel drives without a VROC key. You can also create a non-bootable RAID0 array with the Windows application. VROC is unreliable with non-Intel drives as they drop from the array once in a while.
 
The RSTe / IRSTe terminology is outdated and is now simply called VROC. VROC and CPU Attached RAID are two separate things.

Monstieur

ZoranC
That is great info, Monstieur, thank you for sharing it. Personally I am using Storage Spaces with bifurcated PE4 and 'CPU Attached Storage' option in BIOS disabled. One thing I wasn't able to figure out is if there is any drawback/benefit to using 'CPU attached storage' disabled vs. enabled in such setup, what is technically correct way, because both seemed to work. Do you happen to know answer on that, please? 

The only purpose of CPU Attached RAID is to hide the drives from Windows and remap them into Intel RST to create a RAID array that way or enable Optane Memory Acceleration. For software RAID, always use bifurcation.

Monstieur

ZoranC
I _am_ using bifurcation. Do I interpret your words correctly as when using bifurcation 'CPU Storage Configuration -> CPU attached storage' option should be disabled? If yes that means I am using it correctly but I am little confused by you saying enabling it would hide the drives from Windows as when I had it enabled Windows still saw drives in bifurcated PE4.

The drives would disappear only when you configure RAID in Intel RST. If CPU Attached Storage is disabled, Intel RST will not allow you to configure RAID on those drives if the slot uses CPU lanes. There may be a slight bootup delay due to the unnecessary remapping if you leave the setting enabled.

MonstieurCPU Attached RAID does not work on PE4 anyway, so it will have no effect in your case.

ZoranC

MonstieurYou have to use software RAID in Windows such as Storage Spaces.

BTW, do you have any advanced knowledge of working with Storage Spaces?
 

ZoranC
I currently have 2x NVMe and 2x HDD in two tier (NVMe + NVMe write cache in front of HDD) mirrored setup. I am trying to figure out:
 
1. Is there a way to change size of write cache without tearing whole storage pool apart.
2. How to add more drives to certain tier and how to remove drives from that tier (I'm considering going from 2x 2TB I have in NVMe tier to 4x 4TB, and also going from 2x HDD to 4x HDD)
3. Is there a way to change size of NTFS cluster for volume that sits on that storage pool without tearing apart volume, doing huge backup/restore
4. Once new drives are added how to expand size of current volume

MonstieurThe SSD caching is useless as large sequential writes bypass the cache anyway and write at HDD speed. It's good only for random writes.

Monstieur
I would just get a single large HDD and Optane 905p and use Optane Memory Acceleration. This will accelerate all writes. Just backup your data incrementally with the Veeam agent for Windows (free) or Macrium Reflect to a second HDD.

Monstieur

ZoranC
Are you positive about that? If memory serves me well I did benchmarks after doing this and sequential writes were accelerated too. Granted, I did not build my Storage Pool with Microsoft's default 1GB write back cache, my WBC is 100GB.
 
I was considering Optane path before going Storage Spaces but then Intel handed over development of its software to Microsoft and they limited size of cache to ridiculously low value.

I believe the limit is a 128 KiB buffer for bypassing the cache. There's a white paper about it. You can monitor the Storage Space cache hits in Windows Resource Monitor. File Explorer copies seem to hit the cache most of the time. Sequential writes from other applications typically don't. Any write-through requests also bypass the cache. Optane Memory Acceleration caches everything including write-through because it's basically immune to power loss.
 
You can use any size Optane drive for acceleration with CPU Attached Storage. I'd get a 480 GB or 960 GB drive from eBay.

Monstieur
Yeah, File Explorer does use the cache. Other applications were always slow for me.

Monstieur
I was able to use the full 280 GB cache on my Optane 900p just a few months ago before I got rid of my last HDD. My incremental backups are over 100 GB and they all went straight to cache at maximum speed. The apps are just hosted on the Microsoft Store. There's no indication they aren't being developed by Intel. You can download the native version directly from Intel. The 64 GB limit was for non-Optane SSDs when using Intel Smart Response Technology as a caching solution.

JK_DCthere is not another raid device listed besides the c220/c600 sata driver. There should be another raid controller that accepts the vmd nvme raid driver but it isn't listed.

JK_DC
OK I got 2 670p's in today and put it in the hyper m2 card. I see them in the selection area and can create an array and it says it is bootable. If I enable VROC for the slot it's in I get a 94 error and the pc refuses to POST. If I leave it to non-VROC and I go to disk manager it shows the drives as separate and not in raid at all. If I install the VROC driver it doesn't recognize my sata raid controller but shows the sata drives. It doesn't show the nvme drives at all. I think I have to have the VMD raid driver but it isn't there. I am hoping when I put a VROC key in the slot that it will show the raid device so I can install the driver. It works seamlessly on my AsRock board. It works exactly as you say. So my board might be defective. Are you able to boot the dark with a hyper m2 card in a slot with vroc enabled?