disadvantages of types of cards in mother board ( in brief 3 points )
Answers
In terms of Desktop motherboards:
Aside from the ability to add or upgrade the HDD, a video card, sound cards or any other card peripheral in the appropriate slot, the RAM and (on certain models) the CPU, there's nothing else you can upgrade to the board itself.
In terms of Laptops, it's only the size of the HDD, the RAM, whatever peripheral you choose to plug into the USB slots, and (again, on certain models) the CPU, there’s still nothing else you can add to it.
Upgrading can be very limited depending on what you had in the beginning. If you buy or built your computer and maxed out its capabilities, the only improvements will only be the HDD.
The second problem with motherboards is the components are soldered on the board at the manufacturing plant and they're not meant to be replaced by the user.