So today was apparently a Big Deal Day if you follow Microsoft news, and I'm not going to do a full recap of the event here because by the time you're reading this there are probably already six other posts doing exactly that, with screenshots and everything. I watched about twenty minutes of it on a livestream that kept buffering and then went back to what I was actually doing, which is the thing I want to write about: I've had the Windows 10 Technical Preview running in a VM on this laptop since right before Christmas, and a few people have asked me how to do it without nuking their real install. So here's that.
Why a VM and not a second partition
I know some people dual-boot this stuff. I don't, mostly because I'm lazy and partly because early preview builds do occasionally do weird things to bootloaders, and I don't want to be the guy explaining to his wife why the family desktop won't start on a Tuesday night. A virtual machine means if a build update goes sideways I just roll back a snapshot and pretend nothing happened.
What you actually need
- VirtualBox (I'm on 4.3.20, whatever's current is fine)
- The Windows 10 Technical Preview ISO from the Windows Insider site, which means signing up with a Microsoft account first if you haven't already
- At least 40GB of disk space you don't mind giving up, and 4GB of RAM if you can spare it (2GB technically boots but it's miserable)
- Some patience, because the initial setup and updates are slow in a way that modern Windows really shouldn't be anymore
The actual setup
Create a new VM, type Windows, version Windows 8.1 (there's no Windows 10 option yet in older VirtualBox releases, doesn't matter). Give it 2 CPU cores if you have them to spare. Dynamic VDI disk, 40-60GB, don't bother with fixed size unless you've got room to burn. Mount the ISO, boot, install like you would any Windows version — there's no product key needed for the preview, just hit skip when it asks.
First boot is going to look rough. Enable 3D acceleration in the display settings before you even boot or you'll get stuck at a low resolution with no way to fix it from inside. Then install VirtualBox Guest Additions from inside the VM once you're at the desktop, reboot again, and it actually starts feeling usable.
One thing nobody tells you: take a snapshot right after the clean install, before you install anything else. Insider builds update themselves through Windows Update just like a real release, and every so often a build pushes and something on your machine stops working: a driver, a UI element, whatever. Having a known-good snapshot from before you started poking at it has saved me twice already.
How it's actually holding up
The build I'm running is 9879, from back in December, and honestly the Start menu they brought back is more solid than I expected going in — it doesn't feel like the compromise everyone assumed it would be after the Windows 8 tile thing. That said, search inside the Start menu is still kind of a mess. I typed "notepad" into it three separate times last week and got nothing until the fourth try, on an app that's been installed since the day I set the thing up. Small thing, but it's the kind of small thing that makes a preview feel like a preview.
Given today's event I'd guess a new build lands soon-ish with whatever they were showing off, so if you're going to bother setting this up, now's a reasonable time to do it: you'll have a baseline to compare against once the next one drops. I'm not holding my breath on a specific date though, Microsoft's never been great about that with these things.
Anyway. My coffee went cold while I was writing this and the VM window has been sitting there installing an update for the last eleven minutes. Some things about beta software never change, virtual machine or not.