It is faster to have the Page File on a seperate Hard Drive on a seperate controller but, in all honesty, the speed increase is hardly noticeable. Having games on a seperate HDD on a seperate controller can also increase performance, slightly.
The reasoning is that both hard drives can be written to simultaneously so paging operations and writing to the system files can be done at the same time. This is why a seperate controller is needed, so there is no data collision as if they were running on the same IDE cable.