I had 12.8 installed and checked thru msi afterburner where my gpu's were located.... 6870 master, secondary 6850. Uninstalled 12.8 for 12.9, now 6850 is the master? Also pci slot 1 (6870) runs at 16x and pci 2 (6850)runs x4, could this cause my 6870 to bottle neck since the 6850 is running at...