Microsoft just published an updated graphics driver dated 12/2/2015 that should resolve the 'display adapter stopped responding and has recovered', black screen wake from sleep issue some are experiencing and possibly other related issues. Click 'check for updates' if you prefer not to wait.
If you're on the road a lot and need to keep your SP4 powered this cigarette lighter inverter is a good candidate, has positive reviews, no noisy fan, 3ft cord so can be stowed under seat vs bulky unit that sits in your cigarette lighter and available at your local Walmart or ordered online via Amazon.
http://www.walmart.com/ip/Stanley-F...rter-Bonus-Keychain-LED-Light-Bundle/38243758
If you're on the road a lot and need to keep your SP4 powered this cigarette lighter inverter is a good candidate, has positive reviews, no noisy fan, 3ft cord so can be stowed under seat vs bulky unit that sits in your cigarette lighter and available at your local Walmart or ordered online via Amazon.
http://www.walmart.com/ip/Stanley-F...rter-Bonus-Keychain-LED-Light-Bundle/38243758