The Second Wave: Performance uplift on Windows 10 Always Connected PCs

Windows 10 ‘Always On, Always Connected' PCs with the Snapdragon 835 SoC based on Arm Cortex technology were announced in late 2017. The first wave of 2-in-1 devices from HP, Asus and Lenovo hit the market in early 2018, becoming a disruptive force in a stagnant PC market. We are now set to see the second wave of devices based on the faster, more efficient Snapdragon 850 SoC. 

At the heart of these Windows 10 laptops are big improvements across three significant performance measures – battery life, connectivity and instant on. Consumers are looking for laptop devices that match their smartphone experience, with these three core features all playing an important role in a thin and light form factor, making PCs feel truly mobile. Further performance gains and an improved user experience have been achieved across the second wave of devices with the Snapdragon 850 based on DynamIQ based cores. As noted in the launch blog for DynamIQ, the technology provides advanced compute capabilities, faster responsiveness and increased power savings.

Arm wanted to benchmark the key performance measures, so commissioned Shrout Research, which provides research and consulting services for technology companies, to undertake benchmarking exercises pitting Windows 10 on Snapdragon 2-in-1 devices against other new competitive devices in the market. The full results can be found in a new White Paper, but here’s a summary of what was found.

Battery life

Longer battery life is a key part of providing a truly mobile experience on PCs. The most commonly used performance measures are ensuring a minimum of 20+ hours of usable life or having enough usable battery life to get through full-length transpacific flights. However, evaluating the battery life of a PC is often a more complicated process. During the Shrout Research benchmarking exercises, battery life was measured through two different scenarios – working day tasks and continuous web browsing.

The first scenario – working day tasks – set up a number of different working day tasks that a consumer would face with a PC. These include the following:

  • Idle time: On a Windows 10 desktop with all other windows closed, with LTE and Wi-Fi connected.
  • Web browsing: Using Edge with six tabs open, all with web sites loaded, and the cycle between them being every 60 seconds.
  • Work productivity: Two documents open in Microsoft Word, one spreadsheet open with 50k lines in Excel – typing is entered into the word documents and cells are calculated with percentile measurements.
  • Video conferencing: Skype video and audio calls.
  • Streaming media: YouTube streaming at 1080p30.
  • Screen brightness: All testing was done with the notebook screens at 180 lux brightness.

The per-use-case battery drain for each task was determined by performing it individually on the system and then measuring battery life. From this information a “drain rate” for each device performing each task was calculated. A weight was then applied to each task based on consumer experiences, with this attempting to estimate the amount of time during each working day that a user would perform each of the tasks. The breakdown was as follows:

  • Idle time: 25 percent
  • Web browsing: 25 percent
  • Work productivity: 35 percent
  • Video conferencing: 5 percent
  • Streaming media: 10 percent

When these weights were applied to a ten-hour work day along with the battery drain rates which had been previously calculated, the power draw result was reached which showed how much battery life each device provides over a typical user workday. The notebooks powered by Snapdragon 835 and 850 achieved the best results with lower watts per hour per workday compared to the other devices. In addition, when you look at the estimate workdays between charges, the notebooks powered by Snapdragon again come out on top. In fact, the Snapdragon 850 device showed a 93 percent improvement in battery life compared to the HP Envy x2 powered by Intel.

The second scenario was the more direct in-house developed battery life test developed by Shrout Research, with this attempting to emulate continuous web browsing in Edge under Windows 10. It circulates between 20 different websites, scrolls, and navigates through them on a 30 second timer, then moves onto the next site, repeating the pattern until the battery is drained. This scenario gives us a look at the 'worst case' battery life for a typical user.

Again, the Snapdragon-powered devices come out on top. The Snapdragon 850-based device has the highest amount of battery life under the 'worst case' scenario - 13.5 hours overall - with this being followed by notebook powered by Snapdragon 835 at 10.4 hours.

Testing ‘instant on’

‘Instant on’ is another feature that has been heavily influenced by consumer expectations and their experiences with their smartphones. Just like their smartphone devices, consumers expect PCs to be ‘instantly on’, even when they have been idle for some time. Shrout Research evaluated the ‘instant on’ capability of the notebook devices through measuring the wake-up period after sleep and hibernation.

The testing process involved turning on the devices at the Windows desktop in an idle state, before waiting 15 minutes and attempting to wake them by pressing the power button, recording the time from the button press to the return to the desktop. Just over three hours were then allowed to pass (allowing for the other machines to enter hibernation) before the power buttons were pressed again, with the time being recorded until a return to the desktop.

From sleep, the results are fairly even across the range of notebook devices. However, from hibernation, the clear winners are the Snapdragon-powered devices, with far shorter system wake times. In fact, the hibernation times were the same as the sleep times for the Snapdragon 850 and 835 at 1.4 seconds.

Continuous connectivity

The White Paper notes that there is no clear way to benchmark the impact of continuous connectivity on the Windows 10 devices. Therefore, it explores a number of use cases that demonstrate the advantages of always connected PCs. It can be argued that the availability of Wi-Fi lessens the need for cellular LTE connectivity, but the truth is that free and for-pay Wi-Fi connections still presents plenty of hassle, complexity, and cost to consumers. To a large extent, the only way for a device to be truly ‘Always Connected’ is through cellular connectivity.

Travelling is a constant challenge for connectivity on notebooks, with users facing many different obstacles to remain connected. For example, using airport provided internet connections via Wi-Fi will often require registration, providing a private email address, or even a cell phone message to validate the user before the connection is granted. Moreover, in many airports the connectivity is not free, with users being asked to pay for access while also having a time limit of up to an hour.

Buying a notebook that is always connected via an LTE cellular connection means that users do not have to wait (or pay) for often unreliable, unsecure, and slow Wi-Fi connections. Instead, they can simply open the machine and know that they are already connected, just like you would expect with a smartphone. If you want to see the first-hand experience of seamless connectivity on a Snapdragon-powered device then check out Rene Haas’ blog on his own experience using the HP Envy x2 on Snapdragon 835. At all times, he remained connected to the internet during his commute from London to Cambridge in the UK. Even when the train Wi-Fi dropped off, Rene’s device automatically connected to the LTE cellular connection.

Thinner, lighter, cooler

In addition to battery life, connectivity and ‘instant on’, consumers are looking for thinner and lighter notebook designs that do not generate excessive heat while idle or in use. According to the International Data Corporation Worldwide Quarterly Personal Computing Device Tracker, the ultra slim and convertible PC market is expected to experience 12 percent growth through 2022. The benchmarking exercises did not evaluate the slimness and weight of devices, but did look at the temperatures.

Evaluating the impact of temperature and power efficiency of notebooks is an important indicator of the capability for the processors and platforms to provide consistent and high-quality user experiences. The testing scenario involved utilizing both the CPU cores and GPU core for all competitors by playing back a long-form 4K video from YouTube while also loading up the Windows 10 Store version of Minecraft to run in the foreground. This ensures that as much of each SoC is as active as reasonably possible. The Snapdragon-powered devices performed best with lower temperatures compared to the other notebooks.

An exciting time for PC innovation

After years of stagnation, the PC computing space is witnessing an exciting time for innovation. Windows 10 devices powered by Snapdragon SoC appear to be driving this innovation with multiple features that represent the very best of the smartphone experience – longer battery life, always connected and instantly on. With the performance curve for Moore’s Law reaching its limit, the ability of laptop devices to provide these features will put them at a marked advantage compared to their competitors.

We have just started the journey with our partners in the PC market, and with our recent CPU roadmap announcement the compute performance trajectory will enable even better user experiences for future generations. The fact that we are already seeing performance improvements from the first wave to the second wave of Snapdragon-powered devices proves that we are delivering on our promises. The results from the White Paper further strengthen our belief that Windows 10 devices powered by Snapdragon SoC are leading the way among the new generation of PCs.

Download the White Paper