Thanks for the feedback. I ended up removing both video cards (NVIDIA GeForce 9800 GT's with 512MB RAM each) and replacing with a single GeForce GTX 550 Ti (1024MB of GDDR5.) Everything went smoothly and my games are running nicer now.
2011 E90 328i
2013 F30 328i M-Sport 6MT AW/CR, BMS JB1