Compiz is different on different hardware?

[kek had]

I have installed Dapper flight 4 both at home and at work (I know I should 
not but could not resist the temptation).

At home I have a mid-lowend PC. It is an AMD Duron 2500 + with 1 GB RAM and 
Geforce 5700. At work I have a Xeon HT 2.8 GHz with a Nvidia Quadro Xgl 
graphics card. Needles to say that the graphic card in there is pretty 
awsome.

Now to the question, I have the same distro and the same Compiz, but at home 
I can not find the Scale and switch plugins in the gconf-editor and they do 
not work. At work it is no problem. Why is it different compiz plugins? Are 
they dependent in SSE2 and SSE3 instructions in the Xeon or is it the 
graphics card that can not deliver, so the installation script skips them?

cheers
/K