Intel 200 Series (and X299 and Z370 Series) Chipset Families PCH Datasheet (page 230):
"The PCH SATA controller provides support for Intel Rapid Storage Technology, providing both AHCI and integrated RAID functionality. The RAID capability provides high-performance/data-redundancy RAID 0/1/5/10 functionality on up to six ports for the PCH-H of the PCH SATA controller. Matrix RAID support is provided to allow multiple RAID levels to be combined on a single set of hard drives, such as RAID 0 and RAID 1 on two disks ..."
"2) RST only supports up to six SATA ports."
"RAID Level 0 Performance scaling up to 6 drives ..."etc, etc ... it allows multiple drives in multiple RAID configurations but only supports a maximum of 6 (of the
😎 SATA drives in RAID. It's the same basic HEDT stuff as X99, which was the same basic HEDT stuff as X79, which was the same basic HEDT stuff as X58 - the last time SATA RAID workstations were still economically viable (for Intel's intended market) so the last time Intel pushed to increase maximum SATA RAID capacities.
Other RST versions (RST Premium, RST Enterprise, RST System Acceleration with Intel Optane Technology) exist with enterprise-grade SATA madness, but they won't normally install on consumer HEDT and technical datasheets are hard to find in public domain (although marketing fluff literature is everywhere).
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