What Household Items can be used to Clean Motherboards
...start with re-evaluating your perception that it "needs cleaned." Or stop smoking around your computer. 

As a computer professional, I have pretty much never cleaned a motherboard. Occasionally vacuumed out dust bunnies, but I prefer to locate computers where dust bunnies are less likely to accumulate in them. I have occasionally replaced computers that users spilled things into, and if that (or smoking) is the problem, that is the path to take, not "cleaning" which will be a large time investment for unpredictable results.

What cleaners are suitable is dependent on what the factory that built it chose for a cleaning process, such that they made the components compatible with that solvent. In some modern low VOC processes soap and water and a through rinse / dry is entirely suitable. In the bad old days Freon was a common choice...