LUTZIFER, on 12 December 2012 - 10:55, said:
ASUS HD 7970 DirectCU II: coolest and quietest 28nm card
•Cranked 75MHz over reference for an ultimate engine clock of 1000MHz
•All new DirectCU thermal design utilizes six all-copper heatpipes and 20% bigger dissipation area, achieving 20% cooler and 14dB quieter performance than reference
•Acclaimed DIGI+ VRM with 12-phase Super Alloy Power technology delivers precise digital power and enhanced durability for stable overclocking
•VGA Hotwire allows you to plug and solder wires on the card’s voltage regulators and accurately read and control Vcore, Vmem, and PLL voltages on a hardware level
•GPU Tweak utility helps you modify and tune clock speeds, voltages, and fan performance via an intuitive interface
•One card drives up to six screens with AMD Eyefinity™ 6
It's also 3 times his stated budget.
OP: I can't find a good comparison of cards benchmarked on ACIII, but here's a chart at Anandtech for Batman: Arkham City
@ 1920x1200 and Extreme quality settings. This is a pretty graphically demanding DirectX 11 game, so it should give an idea of relative performance for current/upcoming games.
You can get a GTX 560 Ti or 650 Ti
(bonus: the 650 Ti's are coming with a free copy of ACIII) in your price range which would give you around 50 FPS in Batman @ the above settings.
To drive 3 monitors though, you'll need either an AMD card or an nVidia 600 series card (like the 650 Ti). nVidia's 500 series cards only support 2 monitors from 1 card (excepting some unique configurations that their AIBs designed).