26TB SAS Drive: the Ultrastar HC590, and What to Buy When None Is Listed

Is there a 26TB SAS drive? One, on paper

WD's Ultrastar DC HC590 sheet offers the drive in four versions: 24TB SATA, 24TB SAS, 26TB SATA and 26TB SAS. The same sheet prints the 26 TB capacity as CMR. That makes the HC590 the one 26TB SAS drive we have found documented by its maker.

WD's en-GB product page maps each 26 TB version to a short part number, split by interface and by security option:

The same page gives the full model number WUH722626AL5204 for the 26 TB SAS drive in its SE version. Read the interface before the capacity: 0F59375 and 0F65672 are both 26 TB SE drives, but only the first is SAS. A listing titled 0F65672 is the 26 TB SATA SE drive on WD's map, not SAS.

Seagate and Toshiba 26TB SAS: none found

We have not found a Seagate document listing a 26TB SAS Exos. The SAS table on Seagate's portfolio sheet DS2046.1-2512 runs to 24, 20, 16 and 12 TB, and rates every one of those capacities at 285 MB/s maximum sustained transfer at the outer diameter. A search for a Seagate 26TB SAS drive therefore ends, on that sheet, at 24 TB.

Toshiba's MG11 overview tells the same story. Its SAS item row runs from MG11SCA24T down through MG11SCA22T, MG11SCA20T, MG11SCA18T and MG11SCA16T to MG11SCA14T, and we found no 26 TB SAS row in it. At this capacity, SAS is a one-maker question.

26TB SAS hdd price on Amazon.co.uk

The 26TB SAS table holds no listings right now. If the table is empty, the numbers to look for in a title are 0F59375, 0F65638 and WUH722626AL5204. When it is short, a second table lists in-stock 24TB SAS and 26TB SATA drives, each labelled with its interface. Prices are pounds sterling inc VAT.

In-stock alternatives

None of these is the product this page covers: they are what is in stock on Amazon.co.uk beside it right now. Each row says why it is listed. Check the interface, form factor and part number against your system before buying.

WD Ultrastar 26TB SAS: HC590 figures

SAS costs 0.3 W over SATA on both power rows. WD prints the same idle and operating figures for the 24 TB versions as for the 26 TB ones, so the larger drive adds 2 TB for no extra power on the sheet. That is why its idle efficiency is better: 0.23 W/TB for 26 TB SAS against 0.25 W/TB for 24 TB SAS.

For WUH722626AL5204, WD's en-GB page lists dimensions of 147.07mm x 101.6mm x 26.16mm, a weight of 670 g, endurance of 550TB/year and a 5-Year Limited Warranty. That warranty is the maker's statement for the model, and it does not tell you what a particular seller's listing carries. The Ultrastar DC HC590 page sets out the whole family.

No 26TB SAS drive listed: 24TB SAS or 26TB SATA instead

Which alternative fits depends on what you are filling. If the bay must take SAS, the nearest SAS capacity we have found documented is 24 TB, and the HC590 itself comes in 24TB SAS. On WD's sheet that drive draws the same power as the 26 TB version, so stepping down costs you 2 TB of capacity, not watts, and moves idle efficiency from 0.23 to 0.25 W/TB. Our 24TB SAS drive page compares the 24 TB SAS lines in detail.

If capacity matters more than the interface, 26 TB on SATA is the other route, and the HC590 comes that way too, at 5.6 W idle against 5.9 W for SAS. Seagate's knowledge base says SATA drives may be plugged into SAS controllers. Even so, confirm that your backplane and controller documentation list SATA drives before you buy. The 26TB hard drive page covers every interface at this size.

The reverse does not work, so a SAS drive of any capacity is the wrong buy for a SATA-only system. SAS vs SATA explains the two interfaces more fully.

Buying a 26TB drive: returns

Where a trader sells to a consumer, Part 1 of the Consumer Rights Act 2015 applies, and the time limit for the short-term right to reject faulty goods is the end of 30 days unless an exception in the Act applies. That statutory right is separate from WD's warranty.