>assigning my nVidia card as the main driver for Premiere Pro (instead of the standard card)
You MAY need to turn off the onboard graphics "chip" in BIOS
-http://helpx.adobe.com/premiere-pro/kb/error---preludevideo-play-modules.html
-http://forums.adobe.com/thread/1001579
-Use BIOS http://forums.adobe.com/thread/1019004?tstart=0
-link to why http://forums.adobe.com/message/4685328