Hardware Overview and System Performance
The main piece of hardware inside the Google Pixel and Pixel XL is the Qualcomm Snapdragon 821. The Snapdragon 821 is a minor iteration on Qualcomm’s existing high-end SoC, the Snapdragon 820, providing increased CPU and GPU clock speeds along with a 5% bump in power efficiency. The main design of the SoC, including its 14nm FinFET production, remains the same as its predecessor.
While Qualcomm does advertise the Snapdragon 821 as having increased clock speeds, Google hasn’t utilized these improvements in the Pixel and Pixel XL. These phones have a quad-core custom Kryo CPU clocked at 2.15 GHz on two ‘big’ cores and 1.59 GHz on two ‘LITTLE’ cores, along with an Adreno 530 GPU clocked at 624 MHz.
For reference, the Snapdragon 821 can go as high as 2.34 and 2.19 GHz on its big and LITTLE cores respectively, and up to 653 MHz on the GPU. Google has, in essence, underclocked the Snapdragon 821 to match the Snapdragon 820 while retaining the improved power efficiency and other minor improvements to ISP. The Snapdragon 821 also supports the Snapdragon VR SDK, and therefore Google Daydream, unlike the Snapdragon 820.
The Pixel XL comes with 4 GB of LPDDR4 RAM on a 64-bit bus providing 29.8 GB/s of bandwidth. Google has decided to ditch the split-RAM approach of the Nexus 5X (2 GB) and Nexus 6P (3 GB) and go with an increased 4 GB for both devices, which matches current flagship Android devices. Upping the amount of RAM improves the app loading and resuming experience, and should help in VR as well.
Storage is limited to 32 GB in the base model, or you can get 128 GB of storage for $100 more. The lack of a microSD card slot is a disappointment, because 128 GB microSDs cost just $40, however with either model you are guaranteed to get a certain level of NAND performance.
Connectivity is similar to past Nexus handsets: Wi-Fi 802.11a/b/g/n/ac on 2.4 and 5.0 GHz bands with 2x2 MU-MIMO, Bluetooth 4.2, NFC, and GPS+GLONASS. The upgrade to Qualcomm’s integrated X12 LTE modem brings Category 11/9 LTE with up to 3xCA. Google has opted for two models, one for North America with fewer UMTS and but better CDMA support and 17 LTE bands; and another for the rest of the world with 8 UMTS bands and 21 LTE bands. Either phone should work on the majority of LTE networks worldwide, even outside of their respective regions.
The lightweight and optimized nature of Google’s software, combined with a fast SoC, makes the Pixel XL a very snappy piece of hardware. Compared to the Huawei P9 I was using directly prior to receiving my review unit, the Pixel XL felt noticeably faster to use in everyday tasks. Switching apps in particular was lightning fast, and I suspect this is due to improvements in Android 7.1. Animations across the app are smooth as butter, and things just seem to happen very quickly.
The Google Pixel XL does not perform significantly faster or slower than any other Snapdragon 820 device I’ve tested. This isn’t a huge surprise considering Google has downclocked the Snapdragon 821 to match the Snapdragon 820. If anything, the Pixel XL records slightly reduced performance in some system-wide benchmarks due to Google’s mandatory storage encryption, which reduces NAND performance.
Compared to the Snapdragon 810-powered Nexus 6P, the Pixel XL boasts system performance improvements in the 35 to 45 percent range, which is very respectable for a generational upgrade. The Nexus 6P wasn’t slow, but it’s clear the Pixel XL is faster.