Boot configuration

[Lugi2]

hi

I installed Mint nadia 64 cinnamon on an acer 5750g i7 quad core nvidia 540 graphics card

My problem is that after I choose mint to boot the screen goes black and at the top left corner this " _ " symbol is flashing and i can write something

i don't know what the use is and how i can disable it because it takes time and i want to speed up the boot process

if there is a thread or question already plz tell me the link i don't know how i should formulate this question to search for it

thank you very much

Lugi2