XPS 13/15 9530, 9550, 9630 can only reach Thunderbolt 2 speeds over Thunderbolt 3 port.

I also own a 9550 and feel the same :(

Hi splitframe,

Thanks for posting.

Here is some information you may find helpful.  

http://dell.to/2hAsyRT

Hello Robert,

I appreciate the answer and the information provided, but fail to see

how it helps in my case.

Greetings

Have you ruled out a software issue in any way? There are four basic ways to accomplish this.

You can restart the PC with the Thunderbolt device plugged directly to the Port on it's own. Once the PC has restarted,
install the driver that came with the device. If it still doesn't work, then you will need to proceed with one of the
remaining options. .

You can two way swap your HDD (Hard Disk Drive) with one from a similar working system and see if the fault follows
the HDD to a new machine or if the issue stays with your system? Please follow your User Guide for instructions on
removing any hardware parts as the steps change from system type to the system type or you can search on our support
site using terms such as "your PCs model type", "CRU" and "removal" to find a guide specific to your machine.

You can boot from an Ubuntu Live CD (Regardless of the the operating system currently in use on the PC.) and check to
see if you experience the same issue in another OS. Ubuntu live CD's allow you to boot the OS off the CD without
installing it on your Hard Drive. You can download an ISO of the CD on the Download link below. Tap rapidly at the
F12 key when the system boots to the Dell Splash screen and choose the CD/DVD drive option from the boot once menu
that appears.

Ubuntu ISO Download Link.External Link

You can run a factory restore or reinstall your Operating system.

Caution: Carrying out option iv. would be done as a last resort and only done if one of the other two steps couldn't
be done. You MUST back up all data before carrying out this procedure - if you do not data WILL be lost. Any operating
system reinstall or factory restore involves formatting your Hard Disk Drive (HDD). Please refer to the guides on the
Windows portal for further information on these procedures.

Hello Robert,

thank you for pasting the content of the link you posted earlier again.
Like the link before it did not really help me.
To humor you, yes, with the exception of using Ubuntu Live I, indeed, did all
of the above and more. I also checked multiple BIOS/FW versions like 1.1.19
1.2.0, 1.2.14 and 1.2.16. Furthermore I tried my Akitio on another notebook and
reached full speeds there with the SSD as well as with the GPU.
I did these tests before I knew that it is indeed  a Hardware issue.

If you look at this excerpt from the documentation of the chipset that
the XPS 15 uses you will see that if a device is mounted on PCIe Port #15
it is only given two PCIe lanes, if a device is mounted on PCIe Port #13 it can
use up to four PCIe lanes, the two from Port #13 and #15 combined.
Now if you either look at the screenshot from HWInfo64 here or the
BPD file here ( PCI Scope report ) you will see that the Thunderbolt 3
controller is indeed mounted on Port #15 which on its own is not able
to reach 32Gbps (x4.3) speeds, it only reaches 16Gbps (x2.3) which
corresponds to the results I got in all benchmarks or speed tests I made.
But I am sure you knew most of this as you read through the links I provided.

Tobias

Tobias,

At this point, the only alternative I can offer is to contact Tech Support for additonal troubleshooting, repair, and possible replacement.  Thanks.

Would also like to here from Dell about this.

I also have this problem. In the offer wrote up to 40gb/s Thunderbolt 3.

Hey Robert,

I am considering to buy the Dell XPS 15 which comes out this month.

However I will only buy it if the Thunderbolt 3 is fixed.

Can you please urgently confirm if this will be fixed for this model and for the new XPS15 2017?

Best

Markus

They didn't fix it.  This is from a chat I just had with customer support.

9:31:25 PM   Agent TIP_John Du

The New XPS 15 9650 is with the same as 9550 with TB3 port with 2 PCIe lanes.

Robert-P

At this point somebody should pass a message to Frank Azor at XPS/Alienware and suggest that the XPS 13 specs shown on the current (6 Feb 2016) 9360 model page read as follows:

"Leading-edge connectivity: The Thunderbolt™ 3 multi-use Type-C port allows you to charge your laptop, connect to multiple devices (including support for up to two 4K displays) and enjoy data transfers up to 40Gbps, 8 times that of a USB 3.0i."

Since this appears on the page describing the 9360, it suggests that the Thunderbolt 3 connection in the 9360 is capable of transmitting data up to 40GB when there is conclusive proof that it is only using two lanes (2X) and would never achieve those speeds.

Yes, the spec for Thunderbolt 3 says it will transmit data up to 40GB but it is more than disingenuous at this point to keep advertising that the 9360 will achieve those throughput speeds given it's architecture.

I've returned my 9360 and will await further developments before buying again.

MG

James McMinn is sadly right. It's technically in spec and there are scenarios where the port reaches the 40Gbit. The only two grievances I have with Dell is that they advertise with 40Gbit bi-directional. Which for the port/cable itself is still true, but since HDMI and DP are one way ( except for some minor display information data ) there are not protocols left to fulfill these 40Gbit/s. Other than a proprietary solution in alternate mode that is.

Second they really could have posted this in the technical details. Some people want a TB3 port for the sole purpose of connecting a super fast SSD. The fact that even the Precision models are neutered that way as workstations is laughable :(

This is exactly what I was hoping to use the 9360 for. I wanted to connect it to an external TB3 enclosure and use it with a GTX Titan class GPU (and fast SSD) and be assured that I would not be bandwidth limited as I have seen reported elsewhere.

Can anybody confirm that the 9365 changed the number of lanes connected to the external TB3 port to 4 (instead of the 2 lanes in the case of the 9360).?

MG