People have been poring over the bad Windows builds that Microsoft accidentally distributed to members of the Windows Insider program last week, and they've found signs that Microsoft is planning to release yet more variations of Windows 10.

Each Insider build contains a file enumerating all the different SKUs and their respective product keys. The build that was released last week included keys for three new variants: a version of Windows Server 2016 named "ServerRdsh" and two variants of "Windows 10 Pro for Advanced PCs" (one a standard variant, one an "N" variant that omits certain minor features to appease the EU).

It's not immediately clear what "ServerRdsh" means, so the contents of the Server 2016 release are uncertain, but there's a clearer picture of what's in the Windows 10 version thanks to some leaked slides. The slides use a different (temporary) name—Windows 10 Pro for Workstation PCs—bringing to mind the very earliest days of Windows NT where the desktop version was branded "Workstation" to indicate that it was for big, powerful desktop PCs, unlike its low-end Windows 95 sibling. Whether it's for "Workstation" PCs or "Advanced" PCs, the contents appear to be the same: it's a version of Windows 10 designed for high-end, performance systems used for compute- and graphics-intensive workloads.

I, for one, prefer the "Workstation" branding due both to that historical link and a clearer purpose, but expect "Advanced" to be the chosen name precisely because I think the other name is better.

Here is some more info: pic.twitter.com/hL46sQjKeg — TheGrandMofongo (@GrandMofongo) June 5, 2017

The slides enumerate four main features for the Workstation SKU: a "workstation mode" that nebulously optimizes the operating system for these intensive workloads; usage of the ReFS "Resilient filesystem;" support for SMB Direct network adaptors; and extended hardware support to enable the use of four socket systems (up from the two currently supported in Windows 10 Pro) and 6TB of memory (up from 2TB).

The SMB Direct and four socket/6TB features are going to be of niche interest, to say the least: they all require hardware that most people don't have, and it's hardware that tends to be rather expensive. The first two features may, depending on precisely what Microsoft does with them, be more generally useful. Windows 10 already includes support for ReFS, but it's somewhat limited; currently, no version of Windows can boot from ReFS volumes. At present, Microsoft also only recommends that the file system be used in certain workloads such as storing virtual machines (and the file system has certain features designed to enhance this specific workload, such as cloning blocks of data between files). The mention of ReFS for the Workstation SKU may indicate that the file system is now ready—or is going to be made ready—for a wider range of workloads or that perhaps it will be enabled for system/boot volumes.

The workstation mode may similarly be of wider interest depending on exactly what it does and what kind of performance enhancement it provides.

Microsoft's slides say that the development of the Workstation version was driven by partners and members of the Windows Insider program. The slides were aimed at hardware OEMs, so, should the new edition—which is yet to be officially confirmed or announced—make it to market, we might expect to see a range of workstation-class Windows systems that boast more sockets and more memory than we have traditionally seen in this space.

The apparent choice of Pro as the basis is a little surprising, as this is a market where Windows 10 Enterprise (which includes some desirable security features not found in the Pro SKU) would seem a better fit. One hopes that Microsoft will not force potential users of the operating system to have to choose between support for high-end hardware and support for the most robust security.