Aion: System Requiremetns
  Minimum Recommend
CPU:Pentium 4 2.8Ghz
AMD 64 2800+
AMD 64 X2 5000+
Intel Core Duo E6600
RAM: 1GB 2GB
VGA:nVidia gefore 6600
AMD Radeon X1550
 nVidia geforce 7600
AMD Radeon X2600

  
Harddisk
Space
 30 GB
Operating
System
 Windows 2000 (SP4), Windows XP (SP1), Windows Vista
DirectX DirectX 9.0c (2008, 6)

  

An overview of settings and their visual effect:

Antialiasing Bloom Background Texture

Water Shadow Environment Draw Distance
Object Draw Distance Texture Resolution Shader
User Frame Options   
  
Basically lets you save two sets of resolutions so you can turn it on and off real fast. (simular to alt+h in Lineage II but with your own settings)   
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