Overkill can be subjective. What games do you play, and how many FPS do you need for optimal play? I personally need 60 FPS for a game to be enjoyable to play, and 80+ FPS to completely remove simulator sickness issues. In some games, that is easy to achieve, in others it's quite hard.

So, what sort of performance do you have now, and what would you like?
 
Here is a benchmark with the 7850 at 1280x1024.

bf3.jpg


It's a little higher than your project FPS, but I'd think 60 FPS is good. The 7850 may be a good choice, but if you wanted to skimp, you could as well.
 


It's on the high end. It's perfect for cut edge games, but overkill for others. It will also allow it to last longer than a lesser card, and give you the option to upgrade to 1080p and still have respectable performance.
 

Kamen_BG

Distinguished
Yes the HD 7850 1GB is, for the most part just as good as the version with 2GB's of VRAM.There are however exceptions.If you like modding your Skyrim with HD texture packs, then the 1GB version will recieve a bigger FPS hit than the 2GB version.
BUT.I seriously doubt you need any more power than what you already have.In my opinion you'll have a better gaming experiance by upgrading your monitor not your graphics card.
Right now i've got a HD 5770 which is pretty much as fast as a GTX 550 Ti and i can run every new game at decent settings (medium-high) with 50 or more FPS at 1080P.Even Skyrim, when modded and then optimised.
Honestly tell me.When playing, would you see a huge difference between medium and extreme settings
http://cdn2.benchmark3d.com/benchmarks/Sleeping-Dogs-Benchmark/Sleeping_Dogs_IQ_b.gif

And here's a good, cheap monitor for gaming.
http://www.mwave.com.au/sku-27140212-Dell_S2330MX_23_Ultra_Slim_Full_HD_Widescreen_LED_Backlight_Monitor_1920_x_1080