Amazon.com: Dell Studio XPS 1645 Laptops pack the power you need for work or play, Intel Core i7-820QM Quad Core Processor 1.73GHz (3.06GHz Turbo Mode, 8MB Cache), 6GB Dual Channel DDR3 SDRAM
4GB DDR3 1333 PC3-10600 at Amazon.com
Kingston ValueRAM DIMM 240-pin – 1066 MHz PC3-8500 Memory Module 6Gb 3 x 2GB DDR3 RAM Kit at Amazon.com