Setting > general > username : write your number so it be in da link of your account after that i think you can log in by write your number in login then your password.
try it
Am not sure because i never done that BUT i search for this and find out that ASUS K43sj core i 3 2310M can be compitable with Core™ i7 2630QM Processor
check this out
disable integrated graphics from bios so your pc can only read NVIDIA or in device managmend > display > disable integrated graphics
you can alsoe try to open your game setting and see if you can choose between both of them or not
i agree with this opinion too
some time i get this message checksum error too, all i do is take off bios battery and change it with new one and it work perfect for me, after that go to bios and make all default setting, restart and it be good