Ever since Microsoft and Qualcomm announced in December 2016 that full Windows 10 would be coming to ARM processors, the question on everyone's mind has been how well those x86 apps will run. After all, we all know that legacy Win32 apps don't perform well and drain more power than UWP apps, but since they'll be run with emulation, one would assume that the cost would be even greater.
I got a chance to talk with a representative from Qualcomm, Pj Jacobowitz, at CES last week, and the answer is that it won't. I was told that the performance and battery life impact should be the same as it would be on a PC with an Intel processor.
All of the Qualcomm-based PCs that have been announced promise up to 20 hours of active usage, at the least. We won't see these new PCs until the spring though, and I don't have one to review yet (*cough* I'm looking at you ASUS, HP, and Lenovo), so I won't be able to do my own tests until then.
It will also be interesting to see the kind of standby time that these devices get. ARM chips use what's called big.LITTLE architecture, using more powerful cores for tasks that require it, and more efficient cores for tasks that require less. The latter can include syncing notifications in the background while the system is in standby, ultimately saving precious battery life. In other words, if you've ever thrown your laptop in your bag and opened it up to find the battery dead, that won't be a problem anymore.
Another thing that we talked about is 32- and 64-bit apps. I wanted to clear up a few points, because I've heard different things from different OEMs. Initially, there were reports that Windows on ARM wouldn't run 64-bit Win32 apps, but when I spoke with Dell regarding why it wasn't doing anything with ARM, I was told that 32-bit apps are the problem.
The answer is that that's all been worked out. If it runs on an Intel chip, it should run on a Qualcomm chip as well. If you're worried about first-gen kinks though, you can always just wait for Snapdragon 845 PCs, which are coming later this year.
While Microsoft calls this technology 'Windows on ARM', Qualcomm calls it 'Windows on Snapdragon', which is actually a bit of a misnomer. This technology is not owned by Qualcomm, meaning that other ARM chip manufacturers can adopt it as well. Naturally, whichever company wants to do it would have to partner with Microsoft first, as the Snapdragon 835 is the only ARM processor that's listed as supported for Windows 10. Still, a more diverse hardware ecosystem is always worth hoping for.
And that's what makes Windows on ARM so exciting. It's been a really long time since there was a feasible alternative to Intel and AMD on PCs, and it's going to be fun to watch this develop over the course of 2018.