While Ultrabooks are starting to come down in price, the least expensive models cost $700. Enter the $599 HP Envy Sleekbook 6z, a 15-inch laptop that combines the portability of an Ultrabook with the affordability of a mainstream system. This machine should be music to students' ears. Speaking of music, the AMD-powered Envy 6 also comes equipped with Beats Audio. However, does the Sleekbook 6z perform well enough to make the savings worth it?