Update:
Sorry, there may be a current issue with Planetside 2 which is surprising to me since most games work fine. Not sure. I saw a thread in JUNE 2014 that said it was getting a fix in a future update to support Windows 8 properly.
I do know BF4 was coded to make better use of CPU management which is why it ran better on Windows 8 so maybe it has to do with that somehow.
Unsure of the exact issues or whether they still exist.
*Here's a good link that can apparently solve some issues running on W8:
https://forums.station.sony.com/ps2/index.php?threads/launching-issue-in-windows-8-1.194041/