
Dell XPS 9360/9550/9560 and Precision M5510/M5520 Thunderbolt 3 design flaw - miles
https://www.nextpowerup.com/news/32786/dell-xps-9350-9550-have-a-design-flaw-that-causes-thunderbolt-3-ports-to-run-slower/
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miles
Great comment[0] by nando4 yesterday summarizes the issue nicely:

 _I entirely understand your discontent. The XPS 13 /15 was aimed as a Macbook
killer. Indeed 2015 Macbooks ran 16Gbps-TB2 whereas these XPS systems
outwardly surpassed them as 32Gbs-TB3. Unbeknown by their owners, until TB3
PCIe peripherals were released, they actually ran 16Gbps-TB3 via a neutered x2
3.0 link from the TB controller to the root bridge._

 _Yes, Dell did cheap out, using 2014 DSL5110 controllers rather than the
newer DSL6xxx ones. There would have been a tiny increase in TDP running 4
lanes rather than 2, however, it shows a bias towards DP rather than PCIe
traffic down the 40Gbps TB3 channel._

 _I wish it wasn 't so. Finding an argument against Dell in that mix will be
difficult. Intel are more at fault outwardly advertising TB3 as 4 lanes of
PCIe 3.0, then in the details saying it can be between 2-4 lanes of PCIe 3.0.
Good luck if pursuing Intel._

[0] [https://egpu.io/forums/pc-setup/xps-15-9550-not-able-to-
reac...](https://egpu.io/forums/pc-setup/xps-15-9550-not-able-to-reach-40gbps-
over-tb3/paged/4/#post-1083)

