Software RAID. Although Intel's hardware "acceleration" is supposed to be integrated within the X99 PCH, so I'm guessing that the CPU hit is pretty light. My striped RAIDs multiply R/W throughputs about exactly as expected and seem to use < 0.1% CPU resources (as reported by the Windows Task Manager, anyhow, since I haven't yet figured out the linux OS counterparts).

thanks guys, what about the ASRock that claims it has a built in RAID controller? do you think that's really a dedicated RAID controller or same story as with the ASUS Rampage V?

Hewllo

Need to ask ASRock tech support about their products. Built-in or not one is better off with a proper RAID add-in card.

The X99 chipset - at least the DH82031PCH/SLKDE(B1) version used in my RVE, I hear there is another stepping but can find no info - will allow a single RAID 0/1/5/10/JBOD composed of up to six discrete drives/devices. (I know the Intel literature claims otherwise, maybe I didn't install some RST driver properly or something, but I have never been able to get more than a single X99-serviced RAID configuration to operate.) The ASMedia controller can run a RAID 0/1 composed of (exactly) two drives. You can also gain RAID-like performance from PCIe/M.2 SSD devices which use an embedded RAID/RAIN and multiple controllers/banks, these are seen by the motherboard as a single drive even though are they essentially 2-4 (or more) semi-independent drives sharing a single PCB. Many people report setup issues involving RAID boot/system drives on the RVE (and there's no polite way to say this, but I suspect most of them didn't bother to read their user manuals). And RAIDs are usually "broken" when BIOS/firmware updates are applied, it's often possible to rebuild them but always best to back them up beforehand.