Verdict

For a NAS cache or write-heavy pool, the CT4000T705SSD3 is the safer pick - the WDS400T4B0E uses QLC NAND, which wears out faster and slows badly under sustained writes (light, read-mostly use only).

CT4000T705SSD3
Crucial T705 · 4TB · Desktop
$506 ($126.48/TB)
WDS400T4B0E
WD Blue SN5000 · 4TB · Desktop
$443 ($110.69/TB)

Value at a glance

Price / TB
CT4000T705SSD3 $126.48
WDS400T4B0E $110.69
Endurance (TBW)
CT4000T705SSD3 2,400 TB
WDS400T4B0E 1,200 TB

Price history

US · cheapest per day

CT4000T705SSD3 $506 WDS400T4B0E $443
zoomed · drag to zoom
$573 $508 $443 Aug 21 Aug 24 Aug 27 Aug 31 Sep 3 Sep 7
CT4000T705SSD3 WDS400T4B0E
Capacity 4 TB 4 TB
Form factor M.2 M.2
Interface NVMe NVMe
NAND type TLC QLC
Endurance (TBW) 2,400 TB 1,200 TB
DWPD - -
DRAM cache Yes No
Power-loss protection No No
Sustained write - -
Cost / TBW $0.211 $0.369
Price / TB $126.48 $110.69
Buy
$506
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$443
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Highlighted cells mark the stronger spec for a NAS build. Failure rates from Backblaze Drive Stats where available; $/TB uses the cheapest live price. Buy links are Amazon affiliate.

CT4000T705SSD3

No Backblaze failure data for this model.

WDS400T4B0E

No Backblaze failure data for this model.