I have that config on PC2:
  • Main - 0,0 - 1278,1162
  • Slave1 - 1279,0 - 642,387
  • Slave2 - 1279,388 - 642,387
  • Slave3 - 1279,776 - 642,387
Which leaves enough room for the XP bar at the bottom of the screen and a 1 pixel gap between the regions (personal preference there).