Pavillion dv7 wont boot after reassembly 2

my laptop was recently giving me a message about a cooling fan problem, so i disassembled it ( i removed hard drives rams wireless and then removed keyboard and took alook at the motherboard and decided not to touch it and reassembld every thing back ) now when i turn my laptop on it still gives me a message about secondry hard drive fauiler ( i've been getting this message for 4 monthes, not related to the recent issue ) no error message about the fan , but my laptop won't boot not even to bios , i did a startup test the rams and primary disk passed, I did press on the power button 60 seconds while removing the power and the battery but it didn't solve the problem.