Cpu is working, not getting display on monite

Hello,

my internet router and my phone is connected to my cpu as they both work thru internet...
couple of days back i found my cpu was beeping ...like ram beep...and no display....but i didnt do anything
as my internet wi-fi was working as well as my phone......yest i got time and i thought it ram prob so let me
fix it....when i open the cpu my processor fan was running hard cuz of dust i remove d processor clean it and i placed it back as well as i did same wit ram.....still no display on my moniter....and my wifi is also not working......pls help me wit this......