Nothing no one knows?? Thoughts

Start from scratch.  When you push the power button in, does it lock down?  Does pushing the power button in produce a different type of black screen than when there is no power?  Does the screen appear to "blink" about once every second, or not at all?  Is the power light lit?

Sounds to me like you may have a bad power adapter.  Grab yourself a cheap multimeter at your local hardware store and see if your adapter is putting out the voltage that it is supposed to (listed on the back of the adapter).

A misfed cartridge (bad connection or lockout chip activated) will produce a black screen that appears to "blink" about once every second in concert with the red power light as the system attempts to reset itself.

If you don't see even this evidence, then you're probably either breaking down at the power supply or the RF adapter as mentioned above.

Post results.

Hope that helps.