To clean circuit boards I first blow off loose dirt and grime with a compressor. Next its a distilled water + 90% alcohol + vinegar bath. I use a soft bristled brush to clean all the nooks and crannies. Lastly, I remove the boards from the bath, place them on a towel, and hit them with the compressor to remove any moisture.
Sometimes after I remove the board from the cleaning solution, I give to board a generous squirt of alcohol (both sides) to help disperse the water. I don't remove any chips or parts except for relays. Wouldn't' want to trap moisture inside the clear casing. I Usually let the boards sit for a few days but if I'm in a hurry I will hit them with a hair dryer after the compressor. Even then I still don't power on the machine for a few days just to be safe.