The simple answer to this rather obscure query is
that Dell mother boards are-- er--
Dell manufacture computers complete that is the components used are to Dell specification[although may be made a major in the MoBo/HDD etc.,league]
So it wont be an Asus or Chaintech or Foxxconn
although perhaps made by one of those or another.
As good as Dell are- They are the largest manufacturer and supply government and corporations.
And for a home 'user' very good,
- The home tinkerer can be on a very sticky wicket indeed- bacuse very little from the wide wide world of PC components will replace a Dell component.