Did you completely disconnect the unit's power (i.e. unplug power chord)? If not, do so for 15 minutes. You can combine with next step.
How did you attempt to clear CMOS? Did you disconnect the battery and power for 15 minutes? If not, try this.
Did you try powering on holding the power button down for 3 full seconds? If so, did you ever see the Power Button Menu?
If you remove the memory and power on, do you see the power LED flashing? If so, when you reinstall the memory and then power on, does the light go on solid or does it flash?
Hope this helps,
disconeccting the battery did the trick.