monitor , mouse, keyboard and ethernet

im somewht new at this comp stuff... i needed a gaming mobo and i got an asus 939 socket
not bad but used... anyway i got a gforce 8600 video card ...
nothing but problems from start....
anyway i took out mobo and made sure no static stuff and layed it on paper to check and see if board was shorting out.... it wouldnt turn on the monitor still so im thinking it is the mobo... i made sure everything was screwed in and what not ,changed monitor ports on video card....
the day it crashed it was on all day till i turned it off and when i turned back on i got nothing but hdd and fans as i could see from inside and a green light so some of it is comming on just not what i neeed... again it is keyboard(when i plug in ps three lights come on it but when i turn on mobo , nothing) mouse, thernet and monitor... anymore ideas i would like to consider before i purchase a new mobo
i thank you for your input

 

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