While some Dreamcast consoles have 4 Phillips screws on the bottom, my dreamcast has 4 6-pointed star torx screws(which have the same size as the Phillips screws have for the dreamcast). so what kind of screwdriver should I use?
Can't you just buy a set of torx screw heads? If you do a lot of stuff with electronics, you're going to run into them more often than you want to.
Also, if they are the security heads, you can break the pin in the middle and use a standard torx head. I did it to get into my 360 controllers, I can't remember what i used to do it though. It wasn't hard.