iMac stuck in sleep mode

[HockeyDad12]

I have a 17" Intel iMac that I discovered was stuck in sleep mode this morning. My wife informed me that she was having trouble getting the audio to work the night prior. When I attempted to reset it, it makes the usual start up sounds, but the screen is dark and the sleep indicator light remains on. I immediately went to the Apple.com support section for help. I went through the steps to reset the SMC, which did not not appear to help. I then attempted to reset the SMU, which did nothing but cause my fan to turn on full blast. After that, I went through the SMC reset process again and it seems I'm right back where I started. Any help is appreciated. Thanks in advance.