Constant freezing and multiples issues

Hi, i installed El Capitan on my HP Pavilion G7 1170-SB laptop, wich have :

(sorry for my english, i'm learning but i'm french)

→ BIOS F66 (LEGACY)
→ Intel Core I5 2410M 2.3Ghz (->2.9Ghz)
→ Intel HD 3000
→ 4 Go ram DDR3 Samsung (1333mhz)
→ OSX El Capitain

I already asked you to fix my wifi and it's work but, i still have constant freeze and i don't know why but it's start to be very anoying specialy when i take it at school for works (my friends always say me "OLOL MAC"... bref)

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Constant freezing and multiples issues