SanDisk X400 128GB

Enterprise SSD

Part number SD8SB8U-128G · X400 series · 2.5" SATA SSD. If your machine is listed below, this drive is officially supported — not a forum workaround.

X4002.5" SATA SSD

Part of the SanDisk X400 series →

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71
Compatible NAS models
71 Syn · 0 QNAP · 0 Asus · 0 TM
By vendor
128 GB
Listed capacity
SanDisk
Manufacturer
Strong pick as a cold copy

This is an SSD — an excellent cold copy for the off-site slot of a 3-2-1 plan: fast sequential transfer, silent, no moving parts to degrade on the shelf. The one catch is charge retention: a powered-off NVMe/SATA SSD slowly loses charge (weeks to months), which matters for a copy that sits unplugged. Keep the offline copy plugged in for a few hours once a month, or keep the 3-2-1 'other' copy on spinning media instead. Pair it with a scheduled backup job — see the backup software encyclopedia (Veeam, Duplicati, Hyper Backup) and the 3-2-1 rule.

Compatibility verdict

It appears on the official compatibility lists of 71 machines and series — 71 Synology. This is a Enterprise-class drive: rated for heavier sustained workloads than desktop drives. It is a strong pick for a NAS running 24/7, large-array rebuilds or camera workloads, and enterprise lines are also the drives most widely listed across all five vendors' HCLs. No series-level recording rating is on file for this part number yet, so check CMR vs SMR on the exact model before buying for an array.

Compatible NAS models

Synology DS1511+5-bay See its full HCL → Synology DS1512+5-bay See its full HCL → Synology DS1513+5-bay See its full HCL → Synology DS15155-bay See its full HCL → Synology DS1515+5-bay See its full HCL → Synology DS15175-bay See its full HCL → Synology DS1517+5-bay See its full HCL → Synology DS1812+8-bay See its full HCL → Synology DS1813+8-bay See its full HCL → Synology DS18178-bay See its full HCL → Synology DS1817+8-bay See its full HCL → Synology DS2015xs See its full HCL → Synology DS214play2-bay See its full HCL → Synology DS215+2-bay See its full HCL → Synology DS216+2-bay See its full HCL → Synology DS216+II2-bay See its full HCL → Synology DS2411+12-bay See its full HCL → Synology DS2413+12-bay See its full HCL → Synology DS2415+12-bay See its full HCL → Synology DS3611xs12-bay See its full HCL → Synology DS3612xs12-bay See its full HCL → Synology DS3615xs12-bay See its full HCL → Synology DS3617xs12-bay See its full HCL → Synology DS3617xsII12-bay See its full HCL → Synology DS411+4-bay See its full HCL → Synology DS411+II4-bay See its full HCL → Synology DS412+4-bay See its full HCL → Synology DS415+4-bay See its full HCL → Synology DS415play4-bay See its full HCL → Synology DS4164-bay See its full HCL → Synology DS416play4-bay See its full HCL → Synology DS712+7-bay See its full HCL → Synology DS713+7-bay See its full HCL → Synology DS7157-bay See its full HCL → Synology DS716+7-bay See its full HCL → Synology DS716+II7-bay See its full HCL → Synology DS916+4-bay See its full HCL → Synology FS1018 See its full HCL → Synology FS3017 See its full HCL → Synology RS10613xs+ See its full HCL → Synology RS1219+ See its full HCL → Synology RS18016xs+ See its full HCL → Synology RS2211+ See its full HCL → Synology RS2211RP+ See its full HCL → Synology RS2212+ See its full HCL → Synology RS2212RP+ See its full HCL → Synology RS2414+ See its full HCL → Synology RS2414RP+ See its full HCL → Synology RS2416+ See its full HCL → Synology RS2416RP+ See its full HCL → Synology RS3411RPxs See its full HCL → Synology RS3411xs See its full HCL → Synology RS3412RPxs See its full HCL → Synology RS3412xs See its full HCL → Synology RS3413xs+ See its full HCL → Synology RS3614RPxs See its full HCL → Synology RS3614xs See its full HCL → Synology RS3614xs+ See its full HCL → Synology RS3617RPxs See its full HCL → Synology RS3617xs See its full HCL → Synology RS3617xs+ See its full HCL → Synology RS3618xs See its full HCL → Synology RS4017xs+ See its full HCL → Synology RS812+ See its full HCL → Synology RS812RP+ See its full HCL → Synology RS814+ See its full HCL → Synology RS814RP+ See its full HCL → Synology RS815+ See its full HCL → Synology RS815RP+ See its full HCL → Synology RS818+ See its full HCL → Synology RS818RP+ See its full HCL →

Same-capacity alternatives

Other drives listed at 128 GB capacity, ranked by how many machines list them:

Micron MTFDDAK128MBF 123 machines · M600 Micron MTFDDAK128MAY 114 machines · M550 Crucial CT128M550SSD1 114 machines · M550 Transcend TS128GSSD370S 107 machines · SSD370S Samsung MZ-7PD128 100 machines · 840 Pro Kingston SKC400S37/128G 91 machines · SSDNow KC400 SanDisk SD6SB1M-128G 87 machines · X110 SanDisk SD7SB6S-128G-1122 80 machines · X300

Quick answers

Is the SD8SB8U-128G officially compatible with my NAS?

It appears on the official compatibility lists of 71 machines and series — 71 Synology. Every machine page linked below shows the vendor's own list entry, refreshed daily.

Is the SD8SB8U-128G a good NAS drive?

This is a Enterprise-class drive: rated for heavier sustained workloads than desktop drives. It is a strong pick for a NAS running 24/7, large-array rebuilds or camera workloads, and enterprise lines are also the drives most widely listed across all five vendors' HCLs. No series-level recording rating is on file for this part number yet, so check CMR vs SMR on the exact model before buying for an array.

Can I use the SD8SB8U-128G for a 3-2-1 cold backup copy?

This is an SSD — an excellent cold copy for the off-site slot of a 3-2-1 plan: fast sequential transfer, silent, no moving parts to degrade on the shelf. The one catch is charge retention: a powered-off NVMe/SATA SSD slowly loses charge (weeks to months), which matters for a copy that sits unplugged. Keep the offline copy plugged in for a few hours once a month, or keep the 3-2-1 'other' copy on spinning media instead. Pair it with a scheduled backup job — see the backup software encyclopedia (Veeam, Duplicati, Hyper Backup) and the 3-2-1 rule.

What are alternatives to the SD8SB8U-128G?

At the same capacity, the most widely listed alternatives are Micron MTFDDAK128MBF (123 machines), Micron MTFDDAK128MAY (114 machines), Crucial CT128M550SSD1 (114 machines). The full ranked list is below.