Dell is getting to be horrible with custom builds. It used to be you could get an i5 with a higher end graphics card but you can't anymore. In fact, only the 9xx series comes with high end cards now. So you need to take a performance LOSS and a price HIKE to get a decent card!?
What I would recommend doing OP, is to make things a little more cost and energy effective by getting an 8100 with whatever crappy card you can (I think it's the G310) forget the monitor and speakers. So go for this
Go to dell and choose the Studio XPS 8100 Economy
for processor you want the i5 760 (NOT THE i5 670!)
Pick memory and select 4GB Dual channel
No monitor
Then skip to keyboard and pick the logitech mk550 and then mouse and pick "mouse that comes with keyboard"
You should have the price $856.98. You can then checkout unless you want to buy software with purchase.
Then go to Newegg.com and buy these two Items:
Gigabyte GTX 470
http://www.newegg.com/Product/Produc...-320-_-Product
Corsair 650TX
http://www.newegg.com/Product/Produc...9005&Tpk=650TX
This is a PSU to power the added graphics card.
Monitor - 24" ASUS
http://www.newegg.com/Product/Produc...-049-_-Product
If you feel comfortable installing these yourself go for it. It's pretty simple all and all. If not, go to your nearest local computer shop, or Best Buy and ask around for hardware instalation prices. Geek Squad at best buy charges around $80, and your local computer shop should be a little less expensive.
Total cost should be 1546.93
This should be pretty cost effective and energy efficient (for the parts inside it) and give you balanced performance. Keep in mind however complete custom build would save you ~ $400. If you don't want the hassle of ordering the parts and taking them to best buy or wherever, get the 5770 graphics instead of leaving it generic. Then you can upgrade later if you wish. I would still order the monitor off newegg though.