I've been running Xenoblade with the HD texture pack at 4x IR with a GTX 560 Ti - 1gb of vram at 1920x1080 with no slowdowns. But, I'm also not using AA which does give me slowdown, and maybe my CPU is somewhat picking up the slack. I seen that someone mentioned stuttering in this game, and to my understanding, isn't the random stutter in this game due to hard drive access? I remember reading somewhere an SSD "could" help with that, but I unfortunately don't own one to test it as much as I want to 
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