Best graphics card available for the Dell Studio 8100

If you are a big Nvidia fan, then you should consider the GeForce GTX 560 Ti.  It's a pretty decent card and you could find one on Newegg or TigerDirect for around $200.  Stick with a good brand such as EVGA, ASUS, Sapphire, or MSI.

And be sure and go for a good quality - good brand of PSU as well- such as Corsair, Antec, XFX, or PC Power and Cooling.  Don't get a cheapo brand of card or PSU or you'll end up regretting it.  

Although I have a Dell XPS 7100 and not a 8100, I believe the 8100 is regular ATX form factor just like my 7100 is (just double check this before buying).  I changed out the stock 460 watt Dell PSU in my 7100 for a Corsair TX 650 watt, and it works perfectly.  I installed a XFX brand Radeon HD 6950 graphics card (which is crazy powerful), but they are still going for about $250+ on Newegg.  If you are wanting to keep it around $200, you might consider a Radeon HD 6870.  I would actually take the 6870 over the 560 Ti, but it's my personal preference.  I prefer AMD/ATI cards to Nvidia.  Others like Nvidia.

Good brands for AMD cards are XFX, Sapphire, ASUS, MSI, and HIS.  I picked XFX because they have a double lifetime warranty.

Good luck upgrading, and enjoy your Dell.

Studio XPS 7100

AMD Phenom II x6 1090T

8GB DDR3 RAM @ 1333MHz

Western Digital VelociRaptor 7200RPM 1.0GB HDD

HLDTST6X DVD+/-RW + BD-ROM

XFX Radeon HD 6950 2GB “XXX” version

Corsair TX650 watt PSU

LG M2262D FLATRON HD 1080p monitor ________________________________________________________