Lol - my guess is both systems are the same for gaming - they will both be limited by the same graphics card.
I agree with aford - the first is better with regard to CPU and RAM - althought as I mentioned neither will use the full power of the CPU and few games take advantage of more than 3GB of memory - so the rest is more or less wasted for now unless you do heavy multi-tasking.
But your list is missing a key item - the PSU. The biggest impediment to upgrading Dells for gaming - namely getting a larger graphics card latter - is the PSU. I speak as a former Dell owner. You should check the size of PSU on both - and try to get one with at least 500w. My guess is both will have less - with the Studio computer probably having the less of the two.
I assume the second is not from Dell's gaming line because you did not mention it. Dell does put larger PSUs in this line - but charges substantially more for it. Off course, you could plan to upgrade the PSU yourself - just recognize you will hve the added charge.
Also, did the models you are looking at have options for smaller video cards? If so, you might compare the cost - and potential savings - of getting the smallest card possible and purchasing the 4850 - or a larger card - and installing it yourself - if the PSU permits.
You might also take a look at CyberPower PC which sells complete systems but gives you considerable choice over the components and generally the option to purchase quality brand name components.
http://www.cyberpowerpc.com/
I configured an example model of what you can get from CyperbowerPC for $1281 ( as of 8/9/09 - with one $40 rebate to further lower price). Note the quality components used in the mobo, PSU, video card, and CPU heatsink/fan:
CASE: CoolerMaster Centurion 590 RC-590 Mid-Tower Case
Extra Case Fan Upgrade: Maximum 120MM Case Cooling Fans for your selected case
POWER SUPPLY Upgrade: Corsair Power Supplies (650 Watts CMPSU-650TX - Quad SLI Ready)
CPU: Intel® Core™ i7-920 2.66 GHz 8M L3 Cache LGA1366
COOLING FAN : Xigmatek Dark Knight-S1283V Gaming CPU Cooling Fan (Double layer H.D.T. technology for maximum cooling)
MOTHERBOARD: (3-Way SLI Support) GigaByte GA-EX58-UD4P Intel X58 Chipset SLI/CrossFireX Ultra Durable™3 Mainboard Triple-Channel DDR3/1600 SATA RAID w/ eSATA, Dual GbLAN, USB2.0, IEEE1394a, &7.1Audio
MEMORY: 6GB (2GBx3) PC1333 DDR3 PC3 10666 Triple Channel Memory (Corsair or Major Brand)
FREEBIES: None
VIDEO CARD: NVIDIA GeForce GTX275 896MB 16X PCIe Video Card (EVGA Powered by NVIDIA)
Free Game: FREE GAME - Street Fighters IV
HARD DRIVE: Single Hard Drive (1TB (1TBx1) SATA-II 3.0Gb/s 16MB Cache 7200RPM HDD)
Optical Drive: Sony 20X Double Layer Dual Format DVD+-R/+-RW + CD-R/RW Drive (BLACK COLOR)
Optical Drive 2: 16X DVD ROM (BLACK COLOR)
SOUND: HIGH DEFINITION ON-BOARD 7.1 AUDIO
NETWORK: Onboard Gigabit LAN Network
KEYBOARD: Xtreme Gear (Black Color) Multimedia/Internet USB Keyboard
MOUSE: XtremeGear Optical USB 3 Buttons Gaming Mouse
OS: Microsoft® Windows Vista™ Home Premium w/ Service Pack 1 (64-bit Edition)
SERVICE: STANDARD WARRANTY: 3-YEAR LIMITED WARRANTY PLUS LIFE-TIME TECHNICAL SUPPORT
RUSH SERVICE: NO; READY TO SHIP IN 5~10 BUSINESS DAYS
The EVGA 275 video card is a much faster than the 4850. And when you need more power you just slap in another 275 video card and go to SLI. And should you ever need more memory (which I doubt you will as few applications today will use more than 3 GB and the above has 6GB - but should you need more ---) just had more memory in the available slots.
Note that Cyberpower is a much smaller company that does not have the reputation of Dell and I have no personal experience with them. Still the package is so much better and uses quality name brand components and comes with a nice warranty.