Hi,
well, if you had G53SX with FHD, you had higher DPI density because of smaller screen, in 750 it's biger so with same FHD resolution you have smaller DPI
750 got two GPU, integrated intel HD 4600 and GTX8xxM, it's using intel HD for most of 2D, and GTX for 3D graphics, which helps to save battery. unfortunetly intel HD 4600 is as first GPU listed, dxdiag will show it as GPU #1, you must use Optimus or Nvidia panel to override default usage of intel HD, but still in many apps, it will be displayed. I have G56 with both intel and GTX760M, and any benchmark displays intel graphic as main
STATION WAGON PC:
CPU: AMD Phenom II X6 1100T BE / A10 7700K MOBO: ASUS M4A79XTD EVO / ASUS Crossblade Ranger
COOLING: Coolermaster V8 PSU: Chieftec 80P 600W / Corsair RM850
RAM: Kingston HyperX T1 2x4GB DISK: Seagate 1TB, WD Green Caviar 1,5TB
CASE: Cooler Master Elite 330 / Corsair Carbide SPEC02 VIDEO: Asus GTX460 1GB DCU/TOP
G56JR