Hello, I a am VJing for about a year(PC-Resolume) and have plan to by a macbook pro, but have some money limits. For now it seems like: CPU: 2.4GHz HDD: 160Gb 5400rpm RAM: 2Gb Video: 128Mb An there is possibility to upgrade 200Gb 7200rpm or RAM:4Gb, or videocard 256Mb. Which component would more eff...