Hi, I'm looking at the HP g4, but other options are available. I need the following in my laptop.... 1. At least 4GB RAM 2. 500 GB Hard DRive 3. 15.6" screen 4. Good battery, more than 4hrs. 5. NOT TOSHIBA, SAMSUNG, OR ACER/ASUS Can you help me find some laptops. DON'T SAY BUY A MAC BECAUSE I ALREADY HAVE ONE.