With Windows 10 arriving during the "back to school" buying season, hardware OEMs are starting to show off their new Windows 10 systems.

Toshiba's embrace of Windows 10 comes in two parts: a Cortana button on the keyboard and dual array microphones. The Cortana button is the F1 key; pressing it brings up a small Cortana window, and you can speak or type to Microsoft's virtual agent to get things done. Windows 10 has an equivalent shortcut built in—Win-C—so it seems a little superfluous, but the one-button solution may feel a little more comfortable to the many computer users who don't routinely use multi-key shortcuts.

Dual microphones aren't new, and Toshiba has used them in the past. The company's new lineup uses them across the board, from the Satellite C series starting at $394.99 through the Satellite L series starting at $529.99, up to the Satellite S series starting at $719.99, to provide better performance for Cortana's voice recognition and in Skype and similar applications.

Last year, Toshiba was the first to bring a 4K laptop to market. This year, it has a number of systems with 4K screens, including what it says is the first laptop to include both a 4K screen and a 360 degree hinge. The Satellite Radius, exclusively available in Best Buy, will come in both 14- and 15-inch flavors, starting at $584.99 and $842.99, respectively, with the 15-inch version including a 4K option. This option will add a few hundred bucks to the price, but certainly looks good.

Being designed for Windows 10, both the Radius systems and Toshiba's other line of 360 degree hinge devices, the Satellite Fusion range, include support for Windows 10's Continuum feature. Fold the screen around far enough and Windows makes the switch from "desktop mode" (Start menu, resizeable windows) to "tablet mode" (Start screen, full-screen apps). While this is only a small detail, this is one of the ways in which Windows 10-specific hardware differs from Windows 8-generation devices; the integration of these hardware and software features is just that little bit tighter.

The standout in HP's new offerings is the Pavilion x2 10t Touch. This is a tearable design: a 10-inch tablet with a hinged keyboard attachment. The specs aren't going to blow anyone away—a Bay Trail Atom processor, 32 or 64GB of eMMC storage, 2GB RAM, and a 1280×800 screen—but it costs $299.99, and the design is very pleasing indeed. We've only held it briefly, but it feels surprisingly solid and well-built, and the hinged keyboard attachment is a joy. It connects using magnets, comfortably strong enough that you can shake it around by the keyboard without the screen falling off. The design is thoughtful; many of the first few generations of this style of device would creak or break if the screen was folded back too far. Not so the x2: push too far and the screen pops off.

As well as being a neat design and a nice price, the x2 has one unusual feature: it has a USB Type C port. While USB Type C is a really big deal, it's still in its infancy, with only a handful of systems and devices supporting it at the moment. The Pavilion x2 joins their number, with a Type C port adjacent to a regular USB 2 type A port. The Type C port takes advantage of one of the port's many features, as it serves double duty, being used both to charge the tablet and connect to other devices.

HP's other new machines are all conventional laptops; they're Envy brand laptops in 14, 15.6, and 17-inch versions, starting at $699.99, $629.99, and $999.99 respectively.

The launch and availability of new hardware and a new operating system used to be straightforward. Microsoft would hit its release to manufacturing (RTM) release, finalizing a build of its software for distribution and pre-installation, and then a few months later there would be an official "launch" signaling retail availability both of boxed copies of the software and new PCs with the new software installed.

That's not happening this time around. The first stable, production build of Windows 10 is expected to be finished this month, and that build will become available to download for people upgrading from Windows 7 or 8 on July 29. This gives OEMs only a few weeks to test, validate, and ship systems with the operating system pre-installed.

As a result of this condensed timeline, we probably won't see a big bang of new releases all on one day. Instead, many of the machines are being released before July 29 and will come with Windows 8.1. The Toshiba Satellite Fusion range is available now, the Satellite C, 15.6-inch Satellite L, and Satellite Radius versions will be available on June 21, with only the Satellite S and 17-inch Satellite L held back until July 29. Similarly, the Pavilion x2 will be available from HP starting July 21, with the other Envy laptops launching some time in July.

Once Windows 10 becomes available to the OEMs, systems with a Windows 10 preinstall will start to displace those with Windows 8.1, but there won't be any immediate switch. Toshiba assures us that it will have Windows 10 inventory available to buy in stores on July 29, but there will still be retailers with Windows 8.1 devices in stock on and beyond that date.

All of these systems are, of course, freely upgradable to Windows 10, so as long as buyers are willing to spend a little time to download and install the upgrade, there won't be any longterm difference. But it all underscores how Windows is starting to work differently; the release of a new version is no longer the event that it once was.