Not my experience on my old 2007 MacBook Pro. I didn’t do anything special when I upgraded, just migrated everything. Wonder if it is processor specific? Jens On Dec 9, 2013, at 1:49 PM, Cat <catsoul at thinkplan.org> wrote: > 2010 13-inch 2.66gz Mac Book Pro 8gb ram > > performed great under Mt. Lion; seeing spotty slow ness under mavericks..reading some scary things on line others with as fast or faster computers also slowed by 10.9 > > are with stuck with this or is there an actual fix? > > giving it a day, maybe 2 before I back grade to Mt. Lion > > thanks for any help > > c > ____ Jens Selvig ...Lost in Montana...