PCIe 4.0, Does It Give More Power in Its Slot than PCIe 3.0?

PCIe is a bus and slot as such, well known to all, but in its different versions we always see significant changes where speed and its changes are praised as a rule. But, although it is also important, what about the energy changes in its use? With the arrival of the new NVIDIA RTXs and their increased consumption, does the fact that we have PCIe 3.0 or PCIe 4.0 on our board affect the power supply of the GPU?

We are used to each new version of PCIe, as a bus, doubling the transfer speed and maintaining backward compatibility. But after the innumerable problems that both AMD and Intel have had to include it in consumer motherboards due to electrical requirements, many of you will surely be faced with the doubt of what has changed with respect to the power supplied.

PCIe 4.0

PCIe 4.0 is just a minor upgrade from PCIe 3.0

PCIe-4.0

The short answer to the initial question is that no, PCIe 4.0 does not manage to offer more watts to the slot than PCIe 3.0, or what is the same, we keep the original 75 watts for any device that is plugged into its slot and is x16.

But then where are AMD, Intel, and chipset makers’ problems with motherboards? and above all, why so much controversy to enable it? Again, the problem is the power, but not the one that is going to consume an external card, but the own one that consumes the components of the motherboard.

As backward compatibility has been promoted for everything related to energy or speed, it has been the small components of the boards that have undergone a change to support the 32 GB / s that we can now enjoy.

Specifically, we are talking about transducers and transceivers, small SMDs , and even chipsets, where their consumption has skyrocketed precisely because of the power requirements that are needed to support PCIe 4.0.

Changing the requirements means ending backward compatibility

pcie-slot-big

And it is that as we well know, all the current pins of any current PCIe slot are in their first 11 contacts. Those 11 contacts are what give 75 watts of power to any connected device, so varying this implies losing backward compatibility at some point.

At least from the theoretical part, since increasing the limit that they can deliver implies redoing the specification, if not totally, partially, something that is not too clear even today. In fact, there is a lot of secrecy with this, since manufacturers want more watts in slot to be able to do without external connectors from the PSUs, but that requires that the motherboards also deliver more current on the same number of pins (24).

Perhaps the key is PCIe 5.0 or PCIe 6.0, but in any case, the change will occur for many more market participants, so it is not to design a standard and launch it, but rather to take into account the actors who are going to work with it, from data centers to any office PC.

At the moment there are no changes, but we will continue to increase in speed and that will again lead to an increase in the price of motherboards until the technology and components are adapted, they are mass produced, companies enter to compete and with this the prices fall , just what will happen when Intel official support.