The public preview version of Windows 8.1 expectedly comes with a several bugs, some of which are rather widespread. One such issue that has popped up recently is the one that quickly drains the battery on Surface RT devices.
While Microsoft will quite obviously address this, and all other issues in the final version of the operating system, it seems that this particular bug can be fixed in a rather unexpected way.
Apparently, the battery problems on the Surface RT mostly have to do with the (faulty) Bluetooth drivers. Simply turning it on should fix the problem. A Microsoft support team member has explained this in more detail:
“Powercfg /sleepstudy reports any issues that are preventing the CPU from entering its lowest power state during Connected Standby (e.g. screen is off). In this case, the state of the specific UART controller is preventing the CPU entering its lowest power state.
This UART happens to be connected to the Bluetooth radio on Surface. Unfortunately, the bug that causes this bad state occurs exactly when the Bluetooth radio is turned off in PC Settings.”
If you have deployed Windows RT 8.1 Preview on your Surface RT unit, and are experiencing this issue, then make sure you turn on Bluetooth straight away and see if you notice improvements.
Of course, now that it is nailed, expect Microsoft to fix this in the RTM version of Windows RT 8.1. More details on this could be heading our way later this month.