Yeah, because of fast disks and having 16gb of ram. If your G5 had a 2.5-inch 5400rpm disk and only 2gb of ram, the Mini would likely be faster.
There's also the whole "real world" where not everything is 100% bound to the CPU.
Also if you're using a lot of PPC apps (CS2, Office'04, Poser 6, just as examples) than even a G4 might be faster.
As far as video cards go, the X1900 and the GeForce 6800/7800 are all ancient by now. Unless they're rockin' like a gig of their own memory I wouldn't be surprised if more modern graphics/games would benefit from the fact that a geforce 9400m is just newer and faster on their own, although for the most hardcore of things, shared memory is never the best thing.
Although it's worth noting that things like photoshop CS4 benefit more (although in somewhat silly ways) from a 9400m and purely being faster at framebuffer and some awesome new GPU things photoshop can do, than they ever would from GPUs that don't support some of the awesomest new things, like 6800/7800 and similarly aged ATi GPUs.
There's also the whole "real world" where not everything is 100% bound to the CPU.
Also if you're using a lot of PPC apps (CS2, Office'04, Poser 6, just as examples) than even a G4 might be faster.
As far as video cards go, the X1900 and the GeForce 6800/7800 are all ancient by now. Unless they're rockin' like a gig of their own memory I wouldn't be surprised if more modern graphics/games would benefit from the fact that a geforce 9400m is just newer and faster on their own, although for the most hardcore of things, shared memory is never the best thing.
Although it's worth noting that things like photoshop CS4 benefit more (although in somewhat silly ways) from a 9400m and purely being faster at framebuffer and some awesome new GPU things photoshop can do, than they ever would from GPUs that don't support some of the awesomest new things, like 6800/7800 and similarly aged ATi GPUs.