They have same meaning. (._.)

亲爱Feng !谢谢你！：）

Oh..dear 豆子（효린） ! thanks for your clear Description!

i just want to say,there are some diffrences between the two sentences. for example,if we have finished our breakfast just now,then i asked you "what shall we eat for our lunch?" you may answer:"才刚吃完早饭” that will mean ,you just complain that i was always thinking about eating,although just a joke. here 才 is a stress.才 is stressing for 刚。 才+刚/刚刚/刚才 but 刚才吃完早饭 = had breakfast just now , 刚才=刚=刚刚 thanks~

才刚吃过早饭=刚才刚吃过早饭