I run: i7 w/ 6 gigs RAM Nvidia 660ti 2 gig primary Video Nvidia GTX 285 1 gig dedicated PhysX card Win 7 64-bit Every so often, like a lot of people, I get a crazy frame rate drop to 10-15 fps, whereas I can run maxed to my 60fr refresh rate even in big fights. It seems related to loading towers, big bases or a place with a lot of lifts in a small area and/or a lot of vehicles. I tried making all kinds of tweaks and changes to settings and useroptions. None of that had an effect. By accident during one of these FR drops I alt tabbed out to check teamspeak for something. I noticed when I alt-tabbed back to the game my FPS was normal. Now I do this every time I get the plummet and it works every time. Alt tab out then back again and FR back to normal. If I don't do that my FR stays tanked anywhere from ~1 minute to indefinitely. I had several of my outfit try it when it happens to them and it always works for them too on various sytem configs and settings. I am no programmer, but seems to me like there's a leak, glitch, bug or something related to the loading/un-loading of video assets. As a side-note, I am always CPU bound when this happens. I hope this info helped troubleshoot the problem(s) and gets it fixed.
I noticed tabbing can sometimes restore your FPS too. But I usually fly to the edge of the map and stare out towards to ground/horizon, and it usually always fixes it. It's a memory leak.
