Something seems not accurate in your 1st setup...
Raptors are either 72GB or 150GB. The 72gb is sata ( not sata2 ), but still extremely fast ( i have four of those in 2 stripe raids ). I hear the 150gb is sata2 and 10k rpm, so that's imo the real winner.
If you go that route anyway, you should use the raptor as C: for boot and system + page, the rest ( including My documents folder ) should go to D: .
Also, configuration 1 is clearly a much better gaming machine than option 2...
Jaime

>I have a choice to buy one of these two rather new Dell computers from a reliable source. Please help me weigh out the best option (both are XP SP2 and do not come with monitor)
>
>You'll see that I am basically trying to decide between a Dual Core 3.0Ghz on a 10,000 RPM drive with a second 250GB 7,200 drive for about $400 more than the QUAD core 2.66 Ghz on one single 250GB 7,200 RPM drive. Which configuration is a better (overall faster) developer and and basic power-user stuff (i.e. VFP, Office, Visual Studio 2008? I do not care about the $400, I just want the overall best machine. For some reason the DUAL Core 3.0 Ghz on 10,000 RPM Hard Drive and a separate 250GB 7,00 RPM drive seems better than QUAD Core 2.66 Ghz on one 7,200 RPM Drive. What about the video cards?
>
>System 1:
>-------------------
>Dell XPS 690
>DUAL core Intel Xeon Processor 5160 3.00GHz, 4MB L2,1333
>4 GB Ram
>Primary HD: 80 GB SATA Hard Drive DataBurst 10,000 RPM Sata Western Digital Raptor
>Second HD: 250 GB Sata II 7,200 RPM
>nVidia GeForce 8800 GTS video card
>Price : $2,000
>
>System 2:
>----------------------
>Dell XPS 690
>QUAD core Intel Xeon X5350 2.66GHz 8MB CACHE 1066MHz FSB
>4GB Ram
>250 GB EIDE SATA II Hard Drive 7,200 RPM
>Nvidia GeForce 8400GS PCI EXPRESS VIDEO CARD
>Price: $1,600