Question Pc seems to be powered correctly but no display

[Quickaccount]

After trying to check why my dvd drive made grinding noises i booted up my pc and saw a cmos battery failure screen but the pc proceeded to boot as normally. now after swaping the sata cables of the dvd drive and the hard drive i get no signal, fans are spinning on cpu and gpu and the disk drive is making normal noises. i have now disconnected the dvd drive too, i have tested the hdmi cable connected to the gpu with another device and works fine tested with another hdmi on pc and no signal
I just tried taking out the cmos battery and putting it back in still no signal, the sata cable are now back in the same order
Tried to connect my phone to the usb sockets and th phone will charge but wont display the options of file sharing which normally did.

 

[CountMike]

After trying to check why my dvd drive made grinding noises i booted up my pc and saw a cmos battery failure screen but the pc proceeded to boot as normally. now after swaping the sata cables of the dvd drive and the hard drive i get no signal, fans are spinning on cpu and gpu and the disk drive is making normal noises. i have now disconnected the dvd drive too, i have tested the hdmi cable connected to the gpu with another device and works fine tested with another hdmi on pc and no signal
I just tried taking out the cmos battery and putting it back in still no signal, the sata cable are now back in the same order
Tried to connect my phone to the usb sockets and th phone will charge but wont display the options of file sharing which normally did.

Would be much easier if you included your parts.