7 watts idle – building a low powered server/NAS on Intel 12th/13th gen

Original Article ↗ Hacker News Discussion ↗

Pursuing a 7-watt idle Intel 12th/13th gen build as a home server or NAS highlights how much overall power use depends not just on the CPU, but on chipset behavior, networking, and especially spinning hard drives. Commenters weigh trade-offs between ultra-low idle draw and practical concerns like RAID reliability, ECC memory support, disk spin-down policies, and the cost of modern workstation or server-grade platforms. Alternatives such as Intel N100 mini PCs, used Xeon/Supermicro gear, Synology/QNAP appliances, and ARM-based boards are compared on efficiency, expandability, ease of management, and long-term data integrity.

Low‑Power NAS Design & Idle Consumption

  • Many are impressed by achieving single‑digit watt idle, especially compared to older 24‑bay or Xeon systems idling at 100–150 W.
  • Others note diminishing returns: hardware cost and complexity may outweigh savings vs. a slightly higher idle system used for many years.
  • Several posters describe alternative low‑power builds (e.g., Atom, older Xeon/E3, Ryzen PRO, NUCs, Fujitsu desktops) idling between ~6–50 W depending on disks and cards.

ZFS, RAID, and Spinning Rust

  • ZFS is reported to tolerate long spin‑up delays, but SMR drives can stall for minutes and cause issues.
  • Frequent spin‑up/down is seen as harmful to HDD lifespan; many prefer to keep drives spinning or use long idle timers.
  • Block‑striped RAID (ZFS/Btrfs) makes per‑disk spindown hard; arrays often need most disks for any file.
  • Some use ZFS with spun‑down data vdevs successfully, but it requires careful tuning to avoid background tasks waking disks.
  • Debate over array sizing: some advocate 5–6‑disk RAIDZ with dual parity as a “sweet spot”; others prefer simpler mirrored SSDs or single‑disk + frequent rsync.

ECC Memory and Platform Trade‑offs

  • Strong sentiment that long‑term RAID/NAS without ECC is risky; others respond that many people do it and “it’s fine.”
  • Intel workstation/server chipsets (C246, W680, Supermicro boards) and older Xeons are popular ECC options, though often pricey.
  • AMD Ryzen PRO APUs and some B550 boards can do ECC with the right AGESA/firmware, but verification is non‑trivial.
  • DDR5 on‑die ECC is distinguished from “real” ECC with OS‑visible error reporting.

CPU Choices: From N100 to High‑End Ryzen

  • Many praise Intel N100/N305 mini‑PCs for 2–8 W idle and adequate performance for light NAS, containers, and Home Assistant.
  • Limits: fewer PCIe lanes, RAM caps (often 16–32 GB), and limited SATA make them less suitable for many‑disk ZFS builds.
  • Others showcase high‑end Ryzen (including PRO/embedded) builds tuned for surprisingly low idle given large RAM, 10/40 GbE, and many disks, noting careful component choice is crucial.

DIY vs Appliance NAS

  • Synology/QNAP appliances are lauded for polished DSM‑style software, “set and forget” operation, and long support life, including some ECC‑capable models.
  • Criticisms: closed source, relatively old kernels, limited Btrfs freshness, and finite support windows.
  • Several argue a white‑box NAS with ZFS and ECC offers more control and potentially better long‑term reliability, at the cost of admin effort and Linux/BSD “jank.”