Error! memory cofigured incorrectly. System Halt

That error refers to a hard drive having failed and that needs to be replaced.

It's not connected to the memory configuration error, though - that's a  separate issue.  Unplug the system, disconnect or remove the battery and hold the power button for 30 sec.  Remove and reinstall the memory module(s), if they're removeable.  The see if the system will power up.

If it still won't, and there's more than one module, try one module at a time in each socket until you isolate the bad module (replace it) or the bad socket (in which case a replacement system board will be required).