The reason is flexibility, the board manufacturer can decide how many PCIe lanes to send where, how many USB ports there’s going to be etc. Modern mainboards are a power delivery system and IO backplane.
Yeah but then you can’t switch out the chipset without having a different CPU skew and probably also socket because changing IO without changing up pins doesn’t sound like a good idea. People would barely notice the additional sockets with Intel but we don’t want to take Intel as a benchmark there, do we.
The reason is flexibility, the board manufacturer can decide how many PCIe lanes to send where, how many USB ports there’s going to be etc. Modern mainboards are a power delivery system and IO backplane.
this makes sense but can’t it be done with integrated chipsets too?
Yeah but then you can’t switch out the chipset without having a different CPU skew and probably also socket because changing IO without changing up pins doesn’t sound like a good idea. People would barely notice the additional sockets with Intel but we don’t want to take Intel as a benchmark there, do we.