RPM: WD4005FZBX lists 7200; WD40EZZX lists 5400.
Cache (MB): WD4005FZBX lists 256; WD40EZZX lists 128.
Manufacturer limited warranty: WD4005FZBX lists 5 years (eligible new drives); WD40EZZX lists 2 years (eligible new drives).
Sustained transfer (up to MB/s): WD4005FZBX lists 202; WD40EZZX lists 180.

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 WD4005FZBX and WD40EZZX
Specification	WD4005FZBX	WD40EZZX
Manufacturer	Western Digital	Western Digital
Product family	WD_BLACK	WD Blue
Model number	WD4005FZBX	WD40EZZX
Capacity (TB)	4	4
RPM	7200	5400
Interface	SATA 6Gb/s	SATA 6Gb/s
Recording	CMR	CMR
Cache (MB)	256	128
Form factor	3.5-inch	3.5-inch
Manufacturer limited warranty	5 years (eligible new drives)	2 years (eligible new drives)
Sustained transfer (up to MB/s)	202	180
Physical sector size (bytes)	Not recorded	4096

Compatibility and buying checks

Compare new and renewed offers separately. The manufacturer specification does not guarantee the warranty or return policy of a marketplace seller.

Reviewed 2026-08-21. Published specifications; no independent benchmark or failure-rate claim.

Reviewed 2026-08-21. Published specifications; no independent benchmark or failure-rate claim.