HP media center m7257c won't turn on. Could it be as simple as the on button?

[CoachK]

Hello, My HP is not starting. It is dead, doesn't power up at all. The PSU light on the back of the pc is on, not flashing or off, remains on. Does this mean the psu is working ok?
Could this be a simple change of the power button on the front of the pc to fix this issue? It doesn't appear to be faulty, no sticking. I did the power cord in another outlet. Opened the panel to see if there was anything loose. I don't see any problems. Any help in this matter would be appreciated. Thanks

 

[Tmagic650]

Light or no light on the power supply doesn't matter... Replace the power supply. With an LED on the back of the power supply, it is a HiPro or Bestec supply?

 

[CoachK]

Light or no light on the power supply doesn't matter... Replace the power supply. With an LED on the back of the power supply, it is a HiPro or Bestec supply?

It is a Bestec. Should I go with the same brand or is there something you would recommend? The pc is approx 5 yrs old but other than not turning on, works pretty good. Thanks for the help!

 

[Tmagic650]

This will do you fine. Most likely it will outlast the computer, but serve you well:
Antec Power Supply

 

[CoachK]

I followed your advice. Installed the Antec tonight.
The connector for the hard drive on the original psu had a metal clip, the antec does not (SATA Connector). the connector will not stay in firm. I placed some electrical tape on the side of it. It is seated properly and staying in place. Does it matter which connector I use on a given line. There are 4 available, 2 on 2 different lines.

The pc turns on but I am getting an insert boot disk message. Is this to be expected, or is the hard drive not registering because of the hard drive connection?

thanks