Lombard with power mgt issue?

Due to the fierce loyalty that me and some of my family show to our old macs I couldn't give up on this old thing. I finally took the processor board to work and looked at it with a pretty high powered stereo microscope. I found a lot of debris so I blew it off with some circuit board cleaner. When I put this in the laptop will come up and doesn't go down like it used to.

I do have a strange issue powering it up though... If I don't unplug the battery and the charger after a shutdown - the screen never leaves blackness. As soon as I really cycle the power (the key command reset doesn't do it) the machine powers up and runs normally.

Was there something about a power-management unit?