Motherboard base memory?

Not sure if this would actually go here, but I know this has something to do with the motherboard. Where I work we use software to test every particular piece of hardware in a computer without ever having to load windows, some of you may know what software this is, and there is most likely multiple CD/DVD's that do this. But when ours goes to load up, it will test all the base memory, and if the base memory is to small it will fail to even start-up. Even after a little bit of research, I am able to find nothing on what causes this issue or how it can be resolved. We can obviously remove certain components and test them outside of the machine such as hard drive, and RAM. But it's nice to be able to let it test everything at once, but for some reason we get plagued by this "Base memory to small" issue once every 10 to 20 computers. Anyone have any ideas?