Desktop Memory

XPS Desktops
DDR2-533Mhz  PC2-4200/4300 (600/700/710)
DDR2-667Mhz  PC2-5300/5400 (AIO 19/420/600/630i/700/710/720)
DDR2-800Mhz  PC2-6400 (One 19/AIO 24/420/600/625/630i/720)
DDR3-1066Mhz PC3-8500 (430/435MT/8000/435T/9000/730/730x/Aurora/Area 51)
DDR3-1333Mhz PC3-10600 (430/435MT/8000/730/730x/Aurora/Area 51)
DDR3-1600Mhz PC3-12800 (730x/Aurora/Area 51)
(730x - We do not have plans to add support for PC3-14400 1800MHz, PC3-15000 1866MHz, and PC3-16000 2000MHz memory)

Inspiron Desktops
DDR2-667Mhz  PC2-5300/5400 (518/519/530/531)
DDR2-800Mhz  PC2-6400 (300/400/518/519/530/531/535/537/545/546)
DDR3-1066Mhz PC3-8500 (560/570/580)

Studio Desktops
DDR2-667Mhz  PC2-5300/5400 (Hybrid 140G)
DDR2-800Mhz  PC2-6400 (Hybrid 140G/540/One 1909)