Heatsink: LNM790X004T-RNNNU lists Not included; WDS400T2XHE lists Included.
Endurance (TBW): LNM790X004T-RNNNU lists 3000; WDS400T2XHE lists 2400.
Sequential read (up to MB/s): LNM790X004T-RNNNU lists 7400; WDS400T2XHE lists 7300.
Manufacturer limited warranty: LNM790X004T-RNNNU lists 5 years, subject to manufacturer terms; WDS400T2XHE lists 5 years or TBW limit, whichever comes first.
Sequential write (up to MB/s): LNM790X004T-RNNNU lists 6500; WDS400T2XHE lists 6600.

A larger cache, higher RPM or higher advertised sequential speed alone does not establish which drive is better for your workload.

Specifications side by side

Show differences only

Manufacturer specifications for LNM790X004T-RNNNU and WDS400T2XHE
Specification	LNM790X004T-RNNNU	WDS400T2XHE
Manufacturer	Lexar	Western Digital
Product family	NM790	Black SN850X
Model number	LNM790X004T-RNNNU	WDS400T2XHE
Capacity (TB)	4	4
Heatsink	Not included	Included
Interface	PCIe 4.0 x4 / NVMe	PCIe 4.0 x4 / NVMe
Form factor	M.2 2280	M.2 2280
Cache design	HMB 3.0 and dynamic SLC caching	Not recorded
Endurance (TBW)	3000	2400
Sequential read (up to MB/s)	7400	7300
Manufacturer limited warranty	5 years, subject to manufacturer terms	5 years or TBW limit, whichever comes first
Sequential write (up to MB/s)	6500	6600
NAND	Not recorded	TLC 3D NAND

Compatibility and buying checks

Sequential speeds are manufacturer maxima, not measured game load times. Check your PCIe generation, M.2 dimensions and cooling clearance. The lower of the time or endurance limit normally governs a limited SSD warranty.
Compare new and renewed offers separately. The manufacturer specification does not guarantee the warranty or return policy of a marketplace seller.

Reviewed 2026-09-08. Published specifications; no independent benchmark or failure-rate claim.

Reviewed 2026-09-07. Published specifications; no independent benchmark or failure-rate claim.