The NVIDIA SHIELD Tablet Review

Battery Life

As always, battery life is one of the most important aspects of any mobile device, and is crucial to staying mobile. There’s not much introduction needed to this, as it’s rather well understood that more battery life is usually better. The Shield tablet features an integrated 19.75Wh battery.

This device is a tablet first and foremost, so WiFi browsing battery life is important. In this area, the tablet does well. However, it’s a bit strange how the device performs worse than the Nexus 7 (2013). The reason why I say this is that the Tegra K1 is on a far more power efficient process (28HPm), has broadly equivalent battery capacity to screen area scaling, and should have a more power efficient display due to the reduced gamut. However, it could be that Cortex A15 just isn’t as power efficient as Krait and the silicon backplane of the display isn’t as efficient as the one in the Nexus 7.

While normally web browsing tests are enough to cover the relatively low-compute use cases for smartphones, video playback is a significant use case for tablets. Here, we see that the gap between the Nexus 7 (2013) and the SHIELD Tablet narrows significantly, which can probably be attributed to the mostly display-bound nature of this test. Due to the much lower APL average of this test, we see that the Galaxy Tab S line does noticeably better in this test because their AMOLED displays mean that black-heavy content dramatically reduces power draw. This is because a black pixel in an AMOLED display is turned off and doesn't consume power, while an LCD display relies on a backlight so it isn't possible to turn off the backlight for a single pixel without turning off the entire display.

Of course, the Shield Tablet is also designed for gaming. Unfortunately, the Tegra K1 introduces quite a massive amount of dynamic range. While it’s fully possible for the Shield tablet to last 10 hours of continuous use on a single charge, running the GPU at full blast gives battery life similar to a gaming laptop. Realistically, if a game is made for Tegra K1 and truly stretches the GPU to the limit, battery life is only around two and a half hours, assuming display brightness is kept down to 200 nits. Of course, anything less intensive will do much better.

NVIDIA has also made it possible to cap the maximum frame rate and clock speed for better battery life. However, it’s quite clear in this test that the tablet isn’t capable of sustaining peak performance the way the Shield portable was, as the Shield portable sustained around 90% of the first run performance while the tablet sustained around 80% of its first run performance. The Shield Tablet also has noticeably higher skin temperatures, although this was a subjective observation.