XPS 8930 Thunderbolt bus power

If you open the case and if you see a PSU connection to the Thunderbolt card then it could mean one of two things, that the card needs extra power (not likely) not available on the PCIe bus or that it does supply power to a peripheral device. But if you don't see a PSU connection, power still could be supplied to a peripheral device but that power comes from the PCIe bus. Unfortunately I could not find any detailed information about this card online.

8930 usb-c ports do not provide 25 to 100W power.

Usb-C uses the same connector as thunderbolt.

HOWEVER this does not mean that your system has thunderbolt controller or features.

USB-C Port (that actually only has USB-3.1 behind it).  Thunderbolt 3 is NOT a feature and cannot be added. There is no thunderbolt controller on an 8930.

USB-C  is NOT thunderbolt 3.

https://topics-cdn.dell.com/pdf/xps-8930-desktop_setup-guide_en-us.pdf

https://www.dell.com/support/home/us/en/04/drivers/driversdetails?driverid=tbt79

There may be no Thunderbolt controller on an XPS 8930, but there is an option when ordering the XPS 8930 to add a Thunderbolt 3 PCIe Network and IO Card which the OP apparently has. Whatever that card does, Dell is calling it Thunderbolt 3. The specification for the XPS 8930 do not show the specs of the add in card.

Systems with Optional thunderbolt will have thunderbolt options IN BIOS.

https://www.dell.com/support/article/us/en/04/sln300756/frequently-asked-questions-faqs-about-the-thunderbolt-port-on-a-dell-pc?lang=en

I now own a G7 7588 laptop that has thunderbolt3.  I also purchased an EGPU to experiment with.

https://www.amazon.com/GIGABYTE-Gaming-Graphic-Card-GV-RX580IXEB-8GD/dp/B07CCK527Y/

If the system DOES NOT have Thunderbolt 3 capability, the thunderbolt options will be grayed out and cannot be selected in the BIOS.   A system that DOES NOT and WILL NEVER have an option for thunderbolt 3 will not have any such settings in bios.  This cannot be added later.

Thunderbolt 3 — supports different security levels:

none: No security. The behavior is identical to previous Thunderbolt 1 and 2 versions.

dponly: No PCIe tunnels are created at all, but DisplayPort tunnels are allowed and will work.

user: Connected devices must be authorized by the user. Only then will the PCIe tunnels be activated.

secure: Basically the same as user mode, but additionally a key will be written to the device the first time the device is connected. This key will then be used to verify the identity of the connected device.

Thunderbolt 3 Security Settings

"8930 to add a Thunderbolt 3 PCIe Network and IO Card"

There is no such thing.

This does not exist.

Unfortunately the "cards" that people were adding confused people into believing that there was a way to add a card and get thunderbolt.

Making Thunderbolt3 use the same connector as USB-C also confuses people into thinking a feature is there when its not.

You may encounter an issue where a Dell with a USB Type-C port will not support a connection to a Thunderbolt 3 device (such as a Dell Thunderbolt Dock (TB16). This is a result of either:

• The system does not meet the hardware requirements for Thunderbolt 3
• The system does NOT have the capability and there is no OPTIONAL Thunderbolt 3 controller that can be added later.
  

USB-C is not thunderbolt.  This is not an option that can be added via card.  If motherboard does not have thunderbolt controller it CANNOT BE ADDED.

Even with thunderbolt 2 the way a thunderbolt AIC aka Add in card works is that its a bracket.

There is a GPIO cable that goes from the motherboard to the "thunderbolt card" that passes the thunderbolt signals thru.

http://topics-cdn.dell.com/pdf/precision-t5810-workstation_white-papers3_en-us.pdf

If "There is no such thing" then see here: https://www.dell.com/en-us/shop/dell-desktop-computers/xps-tower-special-edition/spd/xps-8930-se-desktop/xdvsetcr003s?view=configurations&configurationid=4f6da62a-1fb4-4227-93e3-404330205aab

And here is a picture:

Thunderbolt3 PCIe Network and IO Card

"Thunderbolt 3 PCIe Network and IO Card"

is marketing and or mis labeled USB-C network I/O

There is NO SUCH THING as a Thunderbolt 3 card. Any PC any Vendor any OS. DOES NOT EXIST.

Its a header to controller ON the motherboard.

Its either there or its not. CANNOT BE ADDED VIA A PCI-E card. PCI-E cards are mounting brackets for GPIO thunderbolt port.

Q: Can a Thunderbolt 3 dock or adapter work in any system with any USB-C (USB Type C) port?
A: No. Thunderbolt 3 docks and adapters will only work with Thunderbolt 3 USB-C computers and ports. Connecting to a USB-C port without Thunderbolt 3 capability will not work. Note that computers and docks may have a mix of Thunderbolt 3 and other USB-C ports that look very similar. Look for the Thunderbolt icon on both sides of the connection to ensure compatibility.

Thunderbolt 3 cables can work as regular USB-C cables, and vice versa. However, the port on your computer must have a Thunderbolt 3 chip in order to take advantage of the extra features. For example, plugging a USB-C cable into a regular USB-C port and expecting Thunderbolt 3 features is not working ever.

It may be Dell marketing or mislabeling but as I said in a previous post Dell is calling it Thunderbolt 3. That is not my claim. My only claim is there is such a thing, what is does I don't know because I could not find any specifications or other information about the card.

Also Thunderbolt is an Intel trademark so if Dell is using it and not violating trademark laws it should mean something.

Vic, thank you for the reply.  It was helpful that you mentioned that power is available via the PCIe bus.  I wasn't sure about that.  I added a firewire card recently and I had to connect a separate cable from the PSU to it so that it would provide bus power so I thought perhaps that no power was available over PCIe.  But I guess it was just the way my firewire card was designed, in that it doesn't pick up power through the PCIe connection and requires a separate power connection from the PSU.

speedstep, what the Dell sales people told me was that if the PC is configured with this Thunderbolt 3 IO card, then they will build the PC with Thunderbolt 3 capability which can be accessed via the USB-C port on the IO card.  Otherwise, if the PC is not ordered with this card then the PC will not be built with any Thunderbolt capability and therefore adding this card later will not help.

There is no such thing as a " Thunderbolt 3 IO card"

No standard exists for this.

Thunderbolt 3 is a cable to USB-C connector on both ends.

There are ZERO slot interfaces that "ADD" thunderbolt.

Its either there or its not.

This is why Thunderbolt 3 capable port has the lightning bolt icon OR NOT.

This is NOT a feature that can be added.

Nowhere in the SPEC for the 8930 does it say thunderbolt 3 controller on the motherboard.

Nor does it say 40 Gig thruput on ANY of the USB-C ports.

Therefore it DOES NOT HAVE thunderbolt.

Update: Last night I ran Dell Support Assist and it reported that I needed to download and update one driver for my PC.  And that driver was for the Thunderbolt Controller.  So I believe my 8930 does have TB capability, but still not sure whether or not the PCIe TB IO card will supply power to a TB peripheral or not. 

Perhaps instead of repeatedly saying there is no such thing, someone can help the OP with a detailed description of the Thunderbolt 3 Network and IO Card that Dell is selling.

As far as there being no slot interface that add Thunderbolt, this Gigabyte Thunderbolt 3 PCIe card claims to be an Intel Thunderbolt 3 certified add-in card, https://www.amazon.com/GIGABYTE-GC-Titan-Ridge-Thunderbolt-Component/dp/B07GBZL93X/ref=asc_df_B07GBZL93X/?tag=hyprod-20&linkCode=df0&hvadid=320228665853&hvpos=1o3&hvnetw=g&hvrand=8170312752003941521&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9007810&hvtargid=pla-584957974683&psc=1

The specification for the XPS 8930 would not say it has a Thunderbolt 3 controller if it is on an add-in card. The specifications usually lack detail on add-in cards.

"This is why Thunderbolt 3 capable port has the lightning bolt icon OR NOT."

I took a closer look at the IO card that Dell installed.  Just under each of the USB-C ports there is a symbol stamped in the metal....and it happens to be a THUNDERBOLT.

I'm not claiming that Dell gave my PC Thunderbolt capability by simply plugging in this card.  I know it doesn't work that way.  But isn't is possible that they configured and built the PC with Thunderbolt capability to begin with knowing that I paid for this feature, and provided the 40 Gbps speed access with the port on this card?  None of the other USB-C ports on the computer have the lightning bolt icon, but the ports on this IO card do.

@rhythm5

I am not sure why Dell can't add Thunderbolt 3 capability by simply plugging in a card. According to the Thunderbolt Wiki page, https://en.wikipedia.org/wiki/Thunderbolt_(interface), the Intel Thunderbolt controllers uses the PCI Express bus.

The one thing that Dell did do was enhanced Thunderbolt PCIE add-on card support in BIOS version 1.0.8. You can see that if you view the driver details for that BIOS version, https://www.dell.com/support/home/us/en/04/drivers/driversdetails?driverid=mvf0h&oscode=wt64a&productcode=xps-8930-desktop

Again this "ADD IN Card" is nothing more than a bracket to SPECIFIC motherboard with GPIO header. AKA there is a THUNDERBOLT header connection to the motherboard. There are ZERO interfaces from the PCI-E bus to thunderbolt PERIOD END. There is no such standard. H370 series (Support by BIOS F10 or after, PCH PCIe x4 specific slot only) THB-C header cable is like the dell GPIO cable.  Meaning if your motherboard DOES NOT Have Thunderbolt header its NOT EVER WORKING. Most likely explanation for this is Royalty agreements or lack therof meaning nobody is willing to pay INTEL exclusively for the feature and drivers.

THB-C scrapped by Gigabyte

NOTE THB-C HEADER CABLE REQUIRED