Verdict

For a NAS cache or write-heavy pool, the LNM790X004T-RNNNU is the safer pick - the WDS400T4B0E uses QLC NAND, which wears out faster and slows badly under sustained writes (light, read-mostly use only).

LNM790X004T-RNNNU
Lexar NM790 · 4TB · Desktop
$500 ($125.00/TB)
WDS400T4B0E
WD Blue SN5000 · 4TB · Desktop
$443 ($110.69/TB)

Value at a glance

Price / TB
LNM790X004T-RNNNU $125.00
WDS400T4B0E $110.69
Endurance (TBW)
LNM790X004T-RNNNU 3,000 TB
WDS400T4B0E 1,200 TB

Price history

US · cheapest per day

LNM790X004T-RNNNU $500 WDS400T4B0E $443
zoomed · drag to zoom
$500 $471 $443 Aug 21 Aug 24 Aug 27 Aug 31 Sep 3 Sep 7
LNM790X004T-RNNNU WDS400T4B0E
Capacity 4 TB 4 TB
Form factor M.2 M.2
Interface NVMe NVMe
NAND type TLC QLC
Endurance (TBW) 3,000 TB 1,200 TB
DWPD - -
DRAM cache No No
Power-loss protection No No
Sustained write - -
Cost / TBW $0.167 $0.369
Price / TB $125.00 $110.69
Buy
$500
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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.

LNM790X004T-RNNNU

No Backblaze failure data for this model.

WDS400T4B0E

No Backblaze failure data for this model.