AquaMark3 
is a powerful tool to determine reliable information about the gaming 
performance of a computer system. Because the benchmark extensively utilizes 
DirectX9, DirectX8 and DirectX7 functionality, it represents the requirements of 
typical gaming applications in 2003 and 2004.
In 
AquaMark3 the MSI RX600XT-TD128 performs slightly slower than the Gigabyte card 
at stock speeds. I doubt you'd notice it when gaming.
Gun Metal 
2 is one of the first games that will be taking advantage of DirectX 9 
technology. According to Gun Metal 2, 2x AA is enabled by default on all 
videocards and the listed frame rates are average.
Only the 
high end videocards do well in the Gun Metal tests. I suppose being able to push 
about 20 fps is pretty good considering the MSI RX600XT-TD128 is a mainstream 
card.
You 
probably wouldn't want to game with any of these cards at 1600x1200 resolution. 
Frame rates are just too low.