Here are a couple things to watch for on the Dell Studio (at least from the specs I've read online):
Power input center pin, I've read if you don't have this patched correctly in your cable, that the unit will not operate at full CPU speeds. Search.
I would reload the OS with a 32bit for driver compatibility, depends on how you are going to use it. You could also remove some RAM.
I'd replace the hard drive with an SSD and get an external case for the current drive to store your media.