Mac mini stuck in boot cycle
Today my mac mini suddenly froze up while I was working. The screen split vertically and about 1/4 or less of the left side of the screen then showed up on the right. I just had the spinning rainbow wheel and could not force quit applications. I ended up powering off with the power button, then when it tried to reboot, it just kept cycling in the boot cycle and never reach the login screen. I let it go for about 45 minutes like this, hoping that it would eventually "fix itself", but to no avail. I have never had a problem with overheating, but on the off chance that that was it, I let it sit idle for awhile to cool completely, then tried powering up again. While it was off and unplugged, I even tried holding the power button in for 10+ seconds (as I had read elsewhere), to see if that would help when it was plugged in again, but again, when I plugged it back in a powered up, it just cycled and never reached the login screen for me to be able to do anything.
Any suggestions on how to proceed would be greatly appreciated.
Mac mini, iOS 8.3