How thunderbolt 3 USB-C is able to provide 40 Gbit/s ?

[Mohammednt0]

According to Thunderbolt site they claim that TB3 can provide speed Up To 40 Gbit/s !

But TB3 USB-C is configured with 4 PCIe lane designs which can provide only 32 Gbit/s ! (according to wikipedia)

So there is a bottleneck here !! TB3 USB-C should not be able to throughput more than 32 Gbit/s so how they are saying 40 Gbit/s !?

 

[PP Mguire]

40Gb claim is for video data outbound, 32Gb for other data. This bandwidth is not taking into account for the USB3 3.1 Gen 2 controller built in to the Thunderbolt 3 controller. The 40Gb rate limit is mutually there in general for the controller and cable standard, not necessarily all the bandwidth that can be provided. Take for instance a GPU capable of DP 1.4 output, but you're only plugging it into a monitor with DP 1.2, same difference or plugging in a 16x GPU into an 8x open ended slot.

 

[Mohammednt0]

40Gb claim is for video data outbound, 32Gb for other data. This bandwidth is not taking into account for the USB3 3.1 Gen 2 controller built in to the Thunderbolt 3 controller. The 40Gb rate limit is mutually there in general for the controller and cable standard, not necessarily all the bandwidth that can be provided. Take for instance a GPU capable of DP 1.4 output, but you're only plugging it into a monitor with DP 1.2, same difference or plugging in a 16x GPU into an 8x open ended slot.

thank you for answering my question