Best RAID Controllers AI pick
Chosen by an AI model from its trained knowledge, with its reasoning.
AI pick: Broadcom MegaRAID 9500 series 9560-8i
A current hardware RAID controller with onboard cache, CacheVault support and tri-mode SAS/SATA/NVMe ports, backed by mature firmware and management tools.
Not for: ZFS, TrueNAS or Unraid users, who need a plain HBA instead of a RAID card, and home users who would be fine with software RAID.
AI picks by need
For ZFS / TrueNAS / Unraid (HBA, IT mode)
Broadcom SAS 9300 HBA 9300-8i
A SAS3 host bus adapter that passes disks straight to the OS, which is what ZFS and Unraid require.
Not for: Anyone who wants the card itself to do the RAID or has no airflow over the card's heatsink.
For NVMe SSD RAID for workstations
HighPoint SSD7000 series NVMe RAID (line)
Holds several M.2 NVMe drives on one PCIe card for striped arrays without needing a backplane.
Not for: Systems without a free x16 slot that has full lanes, or anyone who needs SAS or SATA drives.
For Older server or budget SAS3 hardware RAID
Broadcom MegaRAID 9300 series 9361-8i
A widely deployed 12Gb/s hardware RAID card with cache and battery/CacheVault options that most server OSes support out of the box.
Not for: Builds that need NVMe drives or PCIe 4.0 bandwidth.
What the AI looks for in RAID Controllers
- RAID vs HBA
- Use a hardware RAID card only if the OS will not manage the disks; for ZFS, Unraid or Storage Spaces use an HBA or a card flashed to IT mode. Software-defined storage needs direct disk access, and a RAID layer hides SMART data and error handling.
- Write cache protection
- For RAID 5/6 with write-back cache, require a battery or supercapacitor module (CacheVault/BBU). Without it, a power loss can corrupt data that was in cache, and the card may force slower write-through mode.
- Interface generation and ports
- Match SAS2 (6Gb/s) vs SAS3 (12Gb/s) vs tri-mode NVMe to your drives, and count drives per SFF-8087/8643 port (4 per port without an expander). The port count and protocol decide how many and which drives you can attach without an expander or backplane.
- Cooling
- Make sure there is direct airflow over the heatsink; these cards are designed for server chassis fans. In quiet desktop cases, RAID and HBA chips overheat and cause drive dropouts or card resets.
- Cables and backplane
- Buy the correct breakout cable (e.g. SFF-8643 to 4x SATA) or backplane cable; forward and reverse breakout cables are not interchangeable. The wrong cable direction or connector type is the most common reason a new card sees no drives.
- PCIe slot
- Use a slot with at least x8 electrical lanes for SAS cards and x16 for multi-NVMe cards. A slot that is physically x16 but wired x4 limits throughput and can disable some NVMe drives on bifurcation-based cards.
Brands that matter
- Broadcom (LSI): Industry standard MegaRAID and HBA lines with the broadest OS and firmware support.
- Microchip (Adaptec): SmartRAID/SmartHBA lines, the main alternative to MegaRAID in servers.
- HighPoint: Focuses on NVMe and SATA RAID cards for workstations and Macs.
- Areca: Long-standing hardware RAID maker with strong management tools.
What to avoid
- Cheap SATA 'RAID' cards that use host-based fakeraid; they offer no protection beyond what OS software RAID already does.
- Hardware RAID cards under ZFS or Unraid.
- Counterfeit LSI/Broadcom cards from unknown sellers; check the board markings and firmware match the claimed model.
- Running a RAID 5/6 write-back array without battery or supercapacitor cache protection.
Questions
What does 'IT mode' mean?
It is firmware that turns an LSI/Broadcom card into a plain HBA that passes each disk straight to the OS, which is what ZFS and Unraid need.
Will a server RAID card work in a desktop PC?
Usually yes in an x8 or x16 slot, but add a fan pointed at its heatsink and check that the motherboard can boot with or skip the card's option ROM.