Fiesta Resolution beyond 1980x1080

[Arika-chan]

I want to ask if somebody managed to run Fiesta on resolutions above 1980x1080 (2560x1600 & 2560x1440), i didn't managed to do it, without some tricks, any suggestions are welcome.

For the Rules...my computer Specs

MoBo: Asus Rampage III Extreme.
Processor: Core i7 980x (OC 5.2 GHz)
RAM: 16 GB DDR3 1066 MHz / 4 GB (OC) 2000 MHz
GPUs: QCFX Radeon HD 5970. (CCC 10.10)
OS: Archlinux (Kernel 2.6.37-rc3), Windows 7 Ultimate X64, Mac OS X 10.6.5, Win XP.

If someone managed to do it plz let me know ^^