BSOD playing League of Legends.

Please provide your system info following this tutorial. System Info - See Your System Specs

Your installation is counterfeit. You have an Acer PID on an ASUS retail motherboard.

Code:

Nome do AnfitriÆo:                            SEBAS-PC  Nome do SO:                                   Microsoft Windows 7 Ultimate 
  VersÆo do SO:                                 6.1.7601 Service Pack 1 Compila‡Æo 7601
  Fabricante de SO:                             Microsoft Corporation
  Configura‡Æo do SO:                           Esta‡Æo de trabalho aut¢noma
  Tipo de compila‡Æo do SO:                     Multiprocessor Free
  Propriet rio registado:                       SebastiÆo
  Organiza‡Æo registada:                        
  ID do produto:                                00426-OEM-8992662-00006 ----> Acer PID
  Data de instala‡Æo original:                  31-03-2013, 20:27:36
  Tempo de arranque do sistema:                 27-06-2014, 15:20:11
  Fabricante do sistema:                        System manufacturer
  Modelo do sistema:                            System Product Name
  Tipo de sistema:                              x64-based PC
  Processador(es):                              1 Processadores instalados.
                                                [01]: AMD64 Family 21 Model 1 Stepping 2 AuthenticAMD ~3600 Mhz
  VersÆo do BIOS:                               American Megatrends Inc.

Counterfeit installations such as yours can contain heavily modified code that causes the installation to behave it unexpected ways. Analysing BSODs and determining their causes on these sorts of installations is very unreliable. For this reason, many analysts won't attempt it.

My recommendation is to install a genuine Windows 7. This will minimise the problems you are experiencing, and make subsequent diagnosis of BSODs far more reliable. Once you are running a genuine Windows 7 installation, and are still experiencing BSOD's, we will be happy to help you solve them.