my friend bought the family pack a few months and i borrowed the installation CD from him, so i could upgrade my tiger to leopard. however, i've experienced sluggish performance since the upgrade (slow boot etc.. on this, i've tried everything. from clearing my caches to resetting the PRAM). anyway, i've searched many forums, and it seems that the problem lies in the fact that i did an upgrade install, instead of an "archive install" or a "clean install". recently, my sis bought a macbook. i was wondering if it's possible to re-install leopard on my machine with the installation CD that came with it. please don't bombard me with the ethical issues on using the same license keys for more than one machine. IMO, apple should have tested the new OS thoroughly b4 churning out 1 upgrage/update after another. i would like to know if there would be any technical problems using the same installation CD. for eg, whether there would be any conflict when me and my sis joins the same network (some softwares such as MWORD do not allow multiple copies of it with the same CD key to be run simultaneously on the same network). or, might any issues arise when we print through the network? thanks.