Your choices are all of the place in the performance and price scale......
1. First pick a card .....
290x outta the box is between a 780 and 780 Ti and that's what ya should be comparing it with not the 760 or 270. Overclocked things change a bit as the 780 has a lot more OC headroom. To get an ideas where the cards sit at "stock" settings, look at the chart for your resolution here
http://www.techpowerup.com/reviews/MSI/GTX_780_Ti_Gaming/24.html
2. Then pick which card type ya want .....
Reference card - nVidia base design
Reference card plus - nVidia base design w/ factory overclock and better cooler (i.e. EVGA SC series)
Factory Overclocked - modified nVidia design with custom PCVB and beefier VRMs (i.e Asus DCII, MSI N gaming Series, Gigabyte Windforce)
Highly Modified - As above with voltage adjustments, multiple BIOSs (I.e MSI Lightning, EVGA Classified)
Each step brings with it an increase in price with the best bang foir the buck coming from the Factory OC'd custom PCB category.
3. Pick ya brand.
There's no solid consistent choice here .... The Asus 780s stand well above the others ..... . For the 780 Ti and 770, I like the MSI .... The EVGA SC is the only one I take pains to avoid and the final choice often depends on which one is on sale atm.
Also.... as the green and red teams have different areas where they excel, ya have to take that into consideration. If you into mining and think mantle has something to offer, then AMD will be the direction for you. If ya see the advantage of Lightboost (and now G-Sync), get a kick outta PhysX, run AutoCAD or like to capture game experiences, (Shadowplay), then nVidia has things you won't get elsewhere.
AT $500, to my mind the Asus 780 is "the bomb" ...kicks tail on the competition here ,......
http://uk.hardware.info/reviews/4639/10/nvidia-geforce-gtx-780-asus-vs-evga-vs-inno3d-vs-msi-conclusion
All four manufacturers - ASUS, EVGA, Inno3D and MSI - made something special out of their GeForce GTX 780. The card that impressed us the most, however, was the ASUS GTX780-DC2OC-3GD5. The new cooler works like charm, and its performance is clearly reflected by the test results. The card also manages to stay very quiet and offers the best overclocking potential thanks to the new cooler. ASUS earns the Gold Award for its card
.
To be fair, MSI new "N" series cards were not reviewed and the MSI 780 is pretty much on par with the Asus. If ya have a few buicks and want to kick it up a notch..... check out the Asus Posiedon which is capable of running under both air and water cooling
http://www.newegg.com/Product/Product.aspx?Item=N82E16814121869
But the Asus 770 offering is a stinker, clocked at only 1058 Mhz when MSI and Giga are up at 1137.