Laptops are not the same as a desktop computer. Desktops have an open architecture where components can be easily swapped.

Laptops are unique to each manufacturer. They are carefully designed to prevent heat issues as they are in a very small form factor and moving air is critical to keep the components from overheating. The motherboards are custom form factors between manufacturers, the graphics cards are usually integrated into the motherboard (even the dedicated solutions are hardwired to the motherboard), the same goes for the sound card.

The only components you can upgrade on a laptop are the processor (in MOST cases), memory and hard drive. Upgrading the processor might not buy you much,as the critical factor might be the type RAM chips. A faster CPU and slow RAM are self defeating, as you do not gain much. In additon, the CPU is often soldered onto the system board. It would be a challenge to remove, except for an experienced tech, who might not even want to try. You also have be careful as there are different kinds of RAM and some kinds might not work in your laptop. If you want a better sound card you can get a PCMCIA version of the Sound Blasters Audigy 2.

Most laptops use a 2.5" hard drive so don't think you can pop a 3.5" drive into it because you can't.