HC590 versus HC580 is the clean WD CMR upgrade comparison. HC590 raises the high-capacity conventional-recording branch to 26TB, while HC580 remains the familiar 22TB/24TB class in much of the live market.
The question is not compatibility risk in the way it is for HC680 or HC690. The question is whether 26TB CMR density is worth the current acquisition premium over HC580 stock.
Choose HC590 when you need the highest WD Ultrastar CMR density and can justify the 26TB price premium. Choose HC580 when existing 22TB/24TB stock is much cheaper per TB or already qualified in your fleet.
Use this as the procurement-level screen before looking at live price rows.
| Decision point | Ultrastar HC590 26TB | Ultrastar HC580 |
|---|---|---|
| Generation role | Newer 26TB CMR branch | Previous 22TB/24TB CMR branch |
| Top capacity in this comparison | 26TB | 24TB |
| Recording | CMR/ePMR | CMR/ePMR |
| Interface | SATA and SAS variants | SATA and SAS variants |
| Cache | 512MB | 512MB |
| Best use | Dense conventional enterprise arrays | Cost-sensitive qualified fleets |
| Main limitation | Newer-drive premium | Lower slot density |
| Decision metric | Premium per extra TB | Discount per TB |
This shows the capacity delta only. The financial answer comes from the live $/TB rows on the page.
| Drive count | Ultrastar HC590 26TB raw | Ultrastar HC580 raw | Raw delta |
|---|---|---|---|
| 4 bays | 104TB | 96TB | 8TB |
| 6 bays | 156TB | 144TB | 12TB |
| 8 bays | 208TB | 192TB | 16TB |
| 12 bays | 312TB | 288TB | 24TB |
No exact in-stock live row is currently matched for WUH722626ALE6L4 / WUH722424ALE6L4. Relevant live alternatives are shown so the page does not collapse into an empty catalogue.
Live prices · updated every 4-5 hours · last checked just now · one side may be unavailable in exact live stock
| Model | Capacity | Recording | RPM | Workload TB/yr | Warranty | $/TB | Price | |
|---|---|---|---|---|---|---|---|---|
| 3TB HUS724030ALS640REFURB | 3TB | CMR | 7,200 | — | — | $15.13 | $45 | Buy |
| 4TB HUS726040ALS210REFURB | 4TB | CMR | 7,200 | — | — | $16.15 | $65 | Buy |
| 3TB HUS724030ALA640REFURB | 3TB | CMR | 7,200 | — | — | $20.00 | $60 | Buy |
| 10TB HUH721010AL5200REFURB | 10TB | CMR | 7,200 | — | 5 yr | $23.50 | $235 | Buy |
| 14TB WUH721414ALE604REFURB | 14TB | CMR | 7,200 | — | — | $24.29 | $340 | Buy |
| 4TB HMS5C4040ALE640REFURB | 4TB | CMR | 7,200 | — | — | $24.75 | $99 | Buy |
| 14TB WUH721414ALE6L4REFURB | 14TB | CMR | 7,200 | — | — | $25.00 | $350 | Buy |
| 14TB WUH721414ALE604REFURB | 14TB | CMR | 7,200 | — | — | $25.00 | $350 | Buy |
Workload rating is recorded per part number from Seagate's datasheet for that exact model, not blanketed across the line — two drives of the same capacity can differ because they are different generations. A dash means the figure is not stated for that listing. Recording technology comes from the manufacturer's published CMR/SMR list; a model absent from that list is shown as UNVERIFIED rather than guessed. Rows priced above 3× this line's in-stock median are flagged and excluded from the winner callout and from every median we compute.
This table is computed from live DatacenterDisk rows when an exact in-stock match exists. It is intentionally blank for unavailable models rather than filled with stale prices.
| Live model | Drive price | $/TB | 100TB raw target | 500TB raw target | 1PB raw target |
|---|---|---|---|---|---|
| No exact in-stock row is available right now. Use the availability table for nearby live alternatives, then re-check the exact model before ordering. | |||||
HC590 is the natural CMR successor when you want more capacity without changing the recording model. Moving from 24TB to 26TB adds about 8.3 percent raw capacity per bay.
That is enough to matter at shelf scale. In 60 bays, the raw difference is 120TB. In a small server, the difference may be smaller than the price premium.
HC580 may already be qualified in existing arrays, and that has value. A drive family that operations already understands can be easier to buy, replace and monitor than a new one.
HC590 earns its place when qualification is complete and the extra density reduces shelves, rack units or power per protected terabyte.
Use HC590 for new dense CMR builds. Use HC580 for replacement pools and cost-controlled expansions where the live market strongly favors 22TB/24TB stock.
If the only reason to consider HC680 or HC690 is a bigger number on the label, stop and read the CMR-vs-SMR comparison first.
Yes. HC590 is WD's high-capacity CMR/ePMR Ultrastar branch.
Two terabytes per bay, or about 8.3 percent more raw capacity.
No. Price per TB is the first screen, not the whole decision. Match recording method, interface, bay count, firmware support, warranty position and rebuild risk before accepting the cheapest row.
Specification claims on this page were checked against the pages below on 1 September 2026. Where a widely-repeated figure did not survive that check, we report what the source says now and say so in the text rather than repeating the familiar number.