$110 HD 7750
$125 HD 7770
$140-$150 HD 6850
$170-$180 HD 6870
$215-$220 GTX 560ti(Some cards,like the galaxy and zotac have a $25-$30 MIR)
$235-$250 HD 7850
$310-$320 HD 7870(some cards like MSI and HIS offer a $20 MIR card)
Have a look at those cards and decide which one you want. Each has its perks. The lower end cards will require less power,but games won't be played on the highest settings. The higher end cards will need a little bit more power,are a little bigger but will give you a great gaming experience.
Hope I helped,
With the games you're playing, it makes no sense to buy anything over a 6870 as COD runs on virtually any system flawlessly.
Video card around that range and really, most video cards won't show a significant change in video and picture quality -- the monitor will be the deciding factor there.
I'd say a 6870 would be your best option here -- it delivers over-average performance(KILLS COD) and at its price range, is undoubtedly the best bang-for-buck card. Try to invest in a better PSU and possibly a CPU upgrade to 2500k -- but a new CPU is not so necessary.
From what I'm reading I cannot overclock the Dell i7-920 @2.67 GHz. It seems as though the options are not available in the BIOS. Is this correct? I'm hoping to play games like Diablo 3, Crysis, Witcher 2, etc. on ultra settings.
If there is a way to properly overclock I'd like to know and thank you.
Well, from what I understand, a company like dell won't give you the option to overclock your CPU, most likely due to the BIOS it has. If you had another motherboard such as ASUS, Asrock, Gigabyte, etc. These companies gives you the option to overclock your CPU.