https://arstechnica.com/gadgets/2017/11/android-8-1-preview-2-activates-pixel-visual-core-with-near-final-build/

Google has posted the second developer preview of Android 8.1. This release brings a "near final" build of Android 8.1 to the Pixel 2 and 2 XL, the Pixel 1 and 1 XL, the Pixel C tablet, and the Nexus 6P and 5X.

The first Android 8.1 Preview, which launched last month, was a bit of a mess. Google's incremental update files didn't work, and then the company had to take them down. The full system images couldn't be flashed on the Pixel 2 for a few days due to needing a new version of the Android Developer Tools that wasn't yet posted. When we did get the files finally flashed, we found out that the headline feature—enabling Google's custom SoC, the Pixel Visual Core—didn't actually work. After a bit of a back and forth with Google, the company confirmed that the the Visual Core would be enabled in the second preview.