VaderPro has got the right idea!
The best way to find out is to adjust the AAS settings and benchmark for each setting.
I'll explain what AAS is, for those who dont know:
It is how much of your system memory (RAM) is allowed to be used by your video card. If your vid card needs to use more memory than what it has on the card, then it can start using the system memory.
A lot of it depends on how much RAM you have and how much applications you run while playing games. If the AAS is being fully used up and other processes are using up all of your RAM, then thats when performance problems will occur.
Another thing to mention is that the AAS is the MAXIMUM that the vid card can use. If the vid card isnt using the AAS, then the rest of the system can use the full amount of RAM.
So, if you dont have a lot of processes running in the background while you are gaming then a high AAS should be fine. Otherwise, just leave it at around 128MB.
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