Titan

Whenever I try to launch any modpack, it takes forever. It says (in the loading bar) that it's verifying stuff. I know it works because I waited like like ten minutes and it finally launched. Anyone have any help? My computer is by no means slow, but I'll still post specs here. Processor 1.8 GHz Intel Core i5 Memory 4 GB 1600 MHz DDR3 Graphics Intel HD Graphics 4000 512 MB Serial Number C02HM59SDRVC Software OS X 10.8.5 (12F45)