Reading your hardware, are you talking about the super/mighty MSI laptops?....I've got the MSI GT683 R model.
It has 2 HD inside, 500 Gb each, it was an extensive task for me, to separate, and make the machine to read them independent.
Of course, and logically, one drive is running win7...certainly, was possible to install PClinux in the other one, but I would say, and in my very poor opinion, that runs with a very low performance, I am a PClinuxOS fan, but seeing the high laptop's potential, I decided to switch to opensuse 12.1_64 KDE.
Man! The laptop's monitor supports all kind of desktop effects, you can play open arena with all the nvidia's power, you can do other things at the same time, and I never have seen, used RAM more than 3 Gb...btw, the machine is able to support 16 Gb RAM...what for?
win7, practically, flies! ....yes! two independent "kingdoms" in one lap!