I haven't used my desktop in over a year because something was wrong. It would start, but only for under a minute. I assumed it was a heat issue and noticed the fan on my power supply wasn't moving. So, I replaced the power supply. Then something else appeared to be wrong so I took it to the shop. They said my mobo was bad and then said my brand new power supply was shot too. I just replaced my mobo tonight and fired it up. It let me get into the setup screen when I pressed f1, or I could continue by pressing f2. First, I pressed f1 and got into the setup screen. Then about a minute later, the computer shut off. I fired it up again and hit f2 this time. I get a message saying, "disk boot failure, insert system disk and press enter." The fan on my power supply is spinning like it's normal. My questions are why us it shutting down and why do I get the message I got?
Any advice would be appreciated.