Computer crashes when i close the game

[Shiara]

Hi guys, im here asking for your help, since the update, every single time i close the game my pc crashes, it got stuk in black and i cant acces event he task manager, i dont know why, because while playing there never was any issue, i can play hours and in multiplayer with not a single problem but when y decide "i had enough of most wanted for today" the computer crashes.. so any ideas how to fix that??

my pc specs are: core i5 2500 @ 3.3, 8gb of ram ddr3 1600mhz, saphire´s ATI RAdeon 7770 vapour edition OC (not tweaked only with the factory oc), and Win 7 at 64