I think Dell is a little pricey. Memory from Crucial.com and some other sellers are gaunteed to work with Dell systems or they take it back. I don't advocate trying to use cheap RAM but why spend more than you need to?
XPS 8100 i7-860(8MB Cache, 2.8GHz), 8GB Dual Channel DDR3 SDRAM @ 1333MHz, 750GB SATA 3.0GB/s 16MB Cache, nVidia GeForce GTS2401GB GDDR3, Dell ST2310 Full HD Widescreen Monitor, AverMedia G2 Combo hybrid TV Tuner, dual 16x DVD+/- RW dbl layer, Microsoft LifeCam Cinema HD, Running Windows 7 Home Premium, 64 bit.
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