I've investigated this issue quite a bit, and it's a bug in how Battlefield 4 interacts with the drivers for the graphics card. The memory usage you see comes from the non paged memory pool. Usually this goes up to about 80/90% when the problem occurs. It can be viewed by opening the task manager and then the tab Performance -> Memory on the left. Normally the 'Non Paged Pool' label says something between 0-200MB at maximum but when this problem occurs, it's 6GB for me. (out of 8GB total system ram).
The error in my case traces back to the driver atikmdag.sys which uses "MINI" as pool tag, but it is entirely possible this issue happens on NVidia cards aswell. Please note that this is still most likely a Battlefield 4 bug, and not a driver bug. There is absolutely nothing we as end users can do about it, so please EA/DICE; fix this.
Having the same issue
Win 8.1 64bit fresh installed yesterday. Came from win 7 and there is no configuration difference except i added a SSD. This problem was not occuring in win7 but is occuring now.
Radeon 6850
4Gb ram
AMD Phenom quad Core
