You could try several things to increase performance.
One thing that is the most obvious is switching to a different DE if your trying to squeeze more out of your hardware, but I doubt that is the issue. Although I have noticed Gnome Shell does work nicely along with other lighter DEs. That isn't really needed though.
Make sure you have the offical most likely proprietary video card drivers installed.
If you are on a laptop you can change the CPU frequency some times it is on a lower mode to conserve power. Jupiter is a nice system tool tray program that makes these changes simple.
You can also try a program called preload which automatically loads system libraries you use often on boot to make doing things faster and since you have a lot of memory this is probably the best way. I have 16GB and thats what I do.
sudo apt-get install preload
Other then that without more details as to what exactly is the issue your having with "performance" it is hard to say.
I know in Unity some things are delayed to make things look nicer by visually fading into place. These settings can be changed if that is what you are referencing.
Give us more information and maybe we can help you better. Throwing out a statement like "I have an awesome machine and Ubuntu sucks" doesn't help us help you.
Hope this helps.