Some thoughts on the MINIMUM system requirements for GalCiv3.
Please note that these are NOT official, it's merely speculation.
GPU
ATi/AMD: Radeon HD2000 series
nVidia: GeForce 8000 series
These are the first generations to support DirectX 10. They were released about halfway through 2007 (about 1.5 years after GalCiv2). Looking at the specifications, I do not think the low-end nor the mid-range cards can provide enough processing power. So a high-end card would be needed Furthermore, considering this isn't going to be a game with simple graphics, I think the cards would need a minimum of 512MiB RAM.
If the minimum recommended requirements would be higher, I think we'd be looking at the HD4000 series for AMD and the GeForce 200 series for nVidia. For both the mid-range models would then probably suffice.
CPU
AMD: Athlon64 X2
Intel: Core2Duo
The 64bit requirement makes these generations the minimum and through some reasonable thinking I came to the conclusion that single-core was probably a no-no. As for the frequencies, For no specific reason I'm thinking 2000MHz for Intel and 2400MHz for AMD would be the recommended minimum. I don't think 'Core i' would be the minimum because A64X2 and C2D still suffice for most tasks nowadays (thus most likely a lot of these systems are still in use*). And don't forget; Stardock is a company that wants to make a big profit and for that you need to sell as much as you can.
Note: A 3GHz Athlon64 X2 (6000+) performs roughly similar to a 2.4GHz Core2Duo (E6600).
Note: first generation Core i3's perform at about the same level of a Core2Duo E8400 (3GHz).
*My system being one of them
RAM
I'm thinking 4GiB would be the minimum simply because in the time of Athlon64 X2/Core2Duo systems, that amount was considered high-end.
So, lets discuss, debate, argue and throw chairs at eachother over these brainfarts of mine.