[SOLVED] Reboot and Select proper Boot Device or Insert Boot Media in selected Boot Device and press a key

[isaiahnewyork11]

I wanted a new graphics card so I bought the PNY GeForce Gtx 1060. I also needed a new PSU so I bought the Corsair CX750m. The new graphics card required 400Watts, so this was an upgrade from my previous 300 watts (now 750 watts). I have a Gateway Dx4860 desktop on Windows 7.

My issue lies with turning on the computer. At first, the monitor would not turn on but my PC would. After that solved, I can not get to my login.

I will get my gateway screen then immediately the error, "Reboot and Select proper Boot Device or Insert Boot Media in selected Boot Device and press a key".
I can get into my boot menu but setting priority to any of the options I do have (Hard disk, EFI device, CD&DVD, Removable Device, LAN) will not work.

I do not have my installation disk, I had this desktop since 2011.

One issue may be the wiring, even though im pretty sure the wires are where they need to be. I would really appreciate any help I can get. If anything, I can provide pictures if necessary. Thank you for your time

 

[popatim]

Make sure the harddrive's two connectors are securely seated.
The smaller one is the data wire and connects down to the motherboard. Be sure that one is seated as well.
The large connector is power and should run back to the power supply. You don't say which power supply you bought so if it is modular therm make sure the power connector is plugged into the proper port on the power supply.