CPU:Always Intel They are reliable and even the cheaper models are efficient GPU:Always NVidia I tried AMD for this laptop and i have been so disappointed.Not even near the NVidia capabilities.
The rest depend on the use you intend to make: Multitasking?-->More Ram Want to load it with stuff?-->More HDD/SSD(There are some HSDD out there,that are basically the medium of these too.Speed of the SSD and capacity of the HDD,plus they are just a bit more expensive than HDD.I would pick a Firecuda model)
I have no knowledge about the rest,but i think this covers the fundementals.