4 Posts
0
1457
Dell Precision 7730 TB3 PCIe Lanes
How many PCIe lanes do the Thunderbolt 3 ports carry? The specs PDF says the PCIe bus is 8 Gbps (two lanes?). That seems very low to me. Less than half the speed of USB 3.1 Gen 2 (20 Gbps).
Speed is one of the primary reasons for wanting Thunderbolt 3. With 8 Gbps I don't think it would even makes sense to use an external GPU.
Can this be right? Am I missing something?
temtem
4 Posts
0
March 28th, 2019 06:00
It seems Thunderbolt is four lanes, but is bottlenecked by the DMI link to the CPU, which has an equivalent bandwidth of four PCIe lanes, but is shared by all the components on the chipset (SSDs, USB, etc).
Better explanation here: http://forum.notebookreview.com/threads/precision-7530-precision-7730-owners-thread.820539/page-197#post-10876207
Thanks to Ionising_Radiation from the notebookreview.com forum. (link)