You must be made of money. Prepare to front $600+ for this.
http://www.crucial.com/store/PartSpe...64X40B&cat=RAM
Those are god damn expensive modules
Btw I am basing this off the requirements of my 4750 with 512mb modules which are: Apacer 512mb PC3200 DDR400 2.5V CL3 200pin SODIMM