You can use eyefinity with different size monitors and screen resolutions. Not a problem. You just need to "order" them in your desired layout within Catalyst. Last, make sure you are using the current drivers from ati.com for your flavor of Windows. Good luck!
No you can't. You can have extended desktops and multi-monitor setups at different resolutions, but the actual eyefinity has to have the same screen resolution on each screen.
I stand corrected. From the Eyefinity FAQ:
Can I support different resolutions?
All monitors running in a Display Group or cloned modes must be running with the same resolution. If monitors have different native resolutions, the highest common non-native resolution between the monitors will be used when creating Display Groups. Monitors running in extended desktop mode can have independent resolutions.
So, you have to use the same res? Can it be 3 different brands? I have a Acer P215H which isn't sold anymore, so could I buy a sony or something, and it work? So could I have 3 different brands of monitors that support the same res?