Default [Q]Whick bootloader I am using??? and Can instal other roms..?!

Hello my friend root my optimus 2x instal recovery etc... and I dont know which bootloader I am using old or new one.
I am on avatar rom 4.2.2 and when I try to instal some other roms it get me back to avatar rom ( I did everything right ) so maybe I am using rom for other bootloader or what so please help..?