Exos generation decision guide

Seagate Exos X24 vs Exos M: Which Generation Should You Buy?

Exos X24 and Exos M overlap at 24TB, but they are not interchangeable labels. X24 offers SATA and SAS plus multiple security variants, while the current Exos M channel range uses SATA HAMR-CMR to extend capacity through 32TB. This guide compares the complete deployment decision.

Exos specifications reviewed August 5, 2026 X18 through Exos M 3+ Generation, interface and model verification required

Quick answer

Choose Exos X24 when you need SAS, specific SED/FIPS variants, a qualified X24 fleet or the tracked 24TB model’s higher published sustained rate. Choose Exos M when SATA is appropriate and current Mozaic generation or 28TB-to-32TB density is the priority. At 24TB, compare ST24000NM002H with ST24000NM001K, not two generic family names.

Overlap capacity24TBExact models have different platforms

X24 interfacesSATA and SASMultiple security variants

Exos M channel range24TB–32TBCurrent data-sheet range

Recording technologyCMR vs HAMR-CMRBoth host as conventional CMR channel drives

Exact model data

Exact 24TB Exos X24 and Exos M models

Capacity	Model	Generation	Interface	Sector format	Security	Recording	Cache	Max sustained	Status
24TB	`ST24000NM002H`	Exos X24	SATA	512e/4Kn FastFormat	ISE	CMR	512MB	285MB/s	Current X24 channel model
24TB	`ST24000NM001H`	Exos X24	SATA	512e/4Kn FastFormat	SED	CMR	512MB	285MB/s	Current X24 channel model
24TB	`ST24000NM007H`	Exos X24	SAS	512e/4Kn FastFormat	ISE	CMR	512MB	285MB/s	Current X24 channel model
24TB	`ST24000NM005H`	Exos X24	SAS	512e/4Kn FastFormat	SED	CMR	512MB	285MB/s	Current X24 channel model
24TB	`ST24000NM006H`	Exos X24	SAS	512e/4Kn FastFormat	SED-FIPS	CMR	512MB	285MB/s	Current X24 channel model
24TB	`ST24000NM001K`	Exos M	SATA	512e/4Kn FastFormat	ISE	HAMR-CMR	512MB	240MB/s	Current Mozaic channel model

The 24TB X24 and Exos M drives must remain separate in pricing and compatibility tables. X24 security and interface variants also use distinct model numbers.

Live catalogue

Current exact-model X24 and Exos M offers

Verified exact-model identity remains eligible for at least 336 hours after successful confirmation. Amazon prices and images refresh separately on 24-hour clocks. If Amazon exposes buying options without one featured numeric price, the card shows Price Options. Generation, interface, capacity, security class and exact model are enforced.

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Checking the current Cloudzat catalogue…

Interactive decision tool

Choose between Exos X24 and Exos M

Match interface, fleet maturity, security and performance priorities to the better starting generation.

Required interface Main priority Planned drive count

The overlap at 24TB creates most of the confusion

Both families have a 24TB SATA option, but X24 ST24000NM002H and Exos M ST24000NM001K are different drives with different platform positioning and published transfer rates. A retailer that groups them under “Exos 24TB” removes information needed for a sound purchase.

Cloudzat uses exact model numbers in every comparison and offer filter. That also prevents a SAS X24 model or SED variant from appearing as though it were the standard Exos M channel model.

Exos X24 is the broader interface and security family

X24 includes SATA and SAS configurations, along with ISE, SED and SED-FIPS variants under separate model numbers. That breadth matters in server environments with SAS backplanes, dual-port requirements, encryption policies or an existing qualification matrix.

If a host requires SAS, the comparison ends quickly: the tracked Exos M 24TB channel model is SATA. Do not use a connector adapter as a substitute for a SAS controller.

Exos M is the density roadmap

The current Exos M channel data sheet spans 24TB, 28TB, 30TB and 32TB. It uses Seagate’s Mozaic HAMR platform while presenting the channel models as conventional CMR SATA drives to the host.

Exos M is therefore attractive when a buyer wants a consistent path above 24TB. It does not require a special HAMR host interface, but the enclosure must still support the exact capacity, sector format and firmware combination.

Published 24TB performance is not identical

The tracked X24 24TB models publish up to 285MB/s maximum sustained transfer, while the current Exos M 24TB channel model publishes 240MB/s. Those are model-specific sequential ratings, not universal application performance.

At array level, controller, workload, network and parity often matter more. Still, the difference is relevant for sequential ingest, rebuild planning and buyers assuming that the newer platform must always have the higher 24TB headline rate.

CMR and HAMR-CMR should not be confused with host-managed SMR

X24 is conventional CMR. Exos M uses HAMR to increase areal density while remaining a CMR channel product. Neither should be grouped with Exos Xz host-managed SMR drives, which require a compatible zoned-storage software stack.

The recording method describes how data is written on the media; it does not remove the need to confirm interface, sector format and exact model.

Sector format and FastFormat

Tracked X24 and Exos M channel models support 512e and 4Kn through FastFormat configurations documented by Seagate. Conversion is destructive and must be planned before the drive contains data.

Choose the format required by the storage platform rather than changing it for theoretical performance. Verify OS, HBA, RAID and NAS support before provisioning a fleet.

Power and thermal design

The data sheets publish model-specific idle and operating figures. Exos M channel models in the current table share published values around 6.9W idle and 9.5W random-read maximum, while X24 figures differ by interface. Use exact values for power-budget planning.

In dense arrays, airflow, ambient temperature and drive-cage design matter more than a small single-drive difference. Validate the warmest bay during rebuild and sustained workloads.

Qualification and operational change risk

A newer generation can create testing work: firmware qualification, monitoring integration, spare strategy and replacement procedures. An established X24 fleet may prefer another X24 drive even when Exos M offers a newer roadmap.

Conversely, a new build with limited bays may benefit from starting on Exos M because it opens 28TB-to-32TB capacity options without changing family later.

Price comparisons must use exact models

Compare ST24000NM002H with ST24000NM001K at the same condition, seller and warranty source. Do not compare a new Exos M listing with a recertified X24 listing and conclude that one generation is inherently cheaper.

Also include array-level cost. A 28TB or 30TB Exos M design may reduce bay count even if its price per terabyte is slightly higher than X24 24TB.

Warranty and seller verification

Mainstream new Exos X24 and Exos M channel data sheets publish a five-year limited-warranty class, but marketplace eligibility can vary. OEM and regional inventory may not follow the expected consumer claim route.

Check the serial number and seller before deployment. Record invoices and delivered labels. Cloudzat does not label a marketplace offer as manufacturer-warranted merely because the family data sheet states five years.

Who should choose each family

Choose X24 for SAS, security-variant breadth, an established X24 qualification or the 24TB model’s higher published sustained rate. Choose Exos M for a new SATA design that values current Mozaic generation and a density path through 32TB.

At 24TB, neither is universally superior. The host, workload, price, warranty route and fleet strategy determine the better drive.

Bottom-line Exos X24 versus Exos M recommendation

Start with interface. If SAS is required, choose the correct X24 SAS exact model. For SATA, compare exact 24TB models, then decide whether X24’s platform maturity and variant choice or Exos M’s current density roadmap matters more.

Do not let a generic 24TB listing make the decision. Use exact model numbers, fresh prices and documented qualification.

How Cloudzat evaluates Exos drives

Cloudzat attaches generation, interface, sector format, security class, recording technology, cache, transfer rate and warranty only to an exact model. Exos X18, X20, X22, X24, Exos M and the verification-required Exos M 3+ records remain separate. This prevents a SATA listing from inheriting SAS specifications or an Exos M drive from inheriting X24 data.

Live offers are screened for new single internal 3.5-inch drives and matched to an exact model. SATA and SAS are kept separate. SSDs, external drives, accessories, enclosures, servers, multipacks, MACH.2, Exos Xz host-managed SMR, other drive families and non-new listings are rejected. Warranty source and delivered-label verification remain essential.

Frequently asked questions

Exos X24 versus Exos M questions answered

Is Exos M newer than Exos X24?

Yes, Exos M is the newer Mozaic/HAMR channel platform. Newer does not automatically mean better for every deployment. X24 offers SAS and more security variants, and an existing X24 fleet may have lower qualification risk.

Is Exos M SMR?

The tracked 24TB-to-32TB Exos M channel models are published as CMR drives using HAMR technology. They should not be confused with Exos Xz host-managed SMR products.

Does Exos M require a special HAMR controller?

The tracked channel models use standard SATA host connectivity. HAMR operates inside the drive. The host must still support the exact capacity, SATA interface and sector format.

Which 24TB model is faster on paper?

The tracked X24 24TB model publishes up to 285MB/s maximum sustained transfer, while ST24000NM001K publishes 240MB/s. Actual array and application performance depends on the full system.

Can I mix Exos X24 and Exos M in one array?

It may be technically possible when interface, sector size and capacity are compatible, but mixed firmware and performance can complicate qualification and support. Follow the array vendor’s policy and test before production use.

Which family supports SAS?

Exos X24 has tracked SAS models. The current Exos M 24TB-to-32TB channel records in this build are SATA. SAS requires a compatible controller or backplane.

Which family has SED or FIPS options?

X24 includes distinct SED and SED-FIPS model numbers. The tracked standard Exos M channel model is ISE. Security requirements must be matched to the exact model and management environment.

Do both families support 4Kn?

Tracked models support FastFormat between 512e and 4Kn, but conversion is destructive and host support must be confirmed. Use the format documented for the platform.

Which family is quieter?

Do not make a family-wide claim from one capacity. Acoustics vary by model, workload and chassis. Both are enterprise drives and can be noticeable in a quiet room.

Which should I buy for a new home server?

For an ordinary SATA server, compare exact prices and ensure cooling and noise are acceptable. X24 24TB can be attractive for mature availability and transfer rate; Exos M becomes compelling when 28TB-to-32TB density is valuable.

Primary sources

Cloudzat may earn a commission from qualifying purchases. Product availability, pricing and specifications can change. Confirm the exact Exos model, generation, interface, sector format, security variant, seller, condition and regional warranty route before buying.