If you upgraded to the Windows 8.1 preview before the RTM was available on your Surface RT, you may have noticed that your connected standby battery life has been significantly reduced. During the preview, turning on (yes, turning ON) Bluetooth acted as a fix.
The problem actually lies within the Wi-Fi performance profiles. If you did not install the 8.1 preview, stop reading this now. During the upgrade from 8.1 preview to RTM, the Wi-Fi profiles are not properly integrated. Rather than issuing a Windows Updates for this huge problem, Microsoft has instead released a quick fix for the problem. You can get it here:http://go.microsoft.com/?linkid=9841873
That wizard will quickly fix the problem. However, it you prefer to do this yourself, open command prompt as an admin and type (copy and paste) the following: powercfg -setdcvalueindex SCHEME_CURRENT 19cbb8fa-5279-450e-9fac-8a3d5fedd0c1 12bbebe6-58d6-4636-95bb-3217ef867c1a 3
Follow that command by entering powercfg -setactive scheme_current
My standby battery life is now back to about 2 or 3 days as it was with 8.0. I hope this helps
The problem actually lies within the Wi-Fi performance profiles. If you did not install the 8.1 preview, stop reading this now. During the upgrade from 8.1 preview to RTM, the Wi-Fi profiles are not properly integrated. Rather than issuing a Windows Updates for this huge problem, Microsoft has instead released a quick fix for the problem. You can get it here:http://go.microsoft.com/?linkid=9841873
That wizard will quickly fix the problem. However, it you prefer to do this yourself, open command prompt as an admin and type (copy and paste) the following: powercfg -setdcvalueindex SCHEME_CURRENT 19cbb8fa-5279-450e-9fac-8a3d5fedd0c1 12bbebe6-58d6-4636-95bb-3217ef867c1a 3
Follow that command by entering powercfg -setactive scheme_current
My standby battery life is now back to about 2 or 3 days as it was with 8.0. I hope this helps