I'm not experienced enough to know if I ought to use specific switches or anything. I'm using "rpmbuild --rebuild --nodeps --target=i686" on the laptop and "rpmbuild --rebuild --nodeps --target=athlon" on the desktop.
If you're going to rebuild all of the packages, do an "everything" install, and don't use --nodeps. Using nodeps may get you incomplete packages, or they may fail to build in any case, but will have taken longer to do so.
