Dell's inability to do the simplest act of providing part numbers for add-on products for Precision Workstation T7920

I’m not affiliated with Dell, but I have the TB3 card in question, which worked for my purposes without a GPIO cable in my 5820.  If you can hang on until tomorrow, I’ll dig the card out and get the part number from it.

btw, I’m having similar issues with my 7960 and Thunderbolt 4 stuff, and can relate entirely.

@johnnyboyc​ Thank you for your reply. It's always nice to know one is not alone in the "deadly desert" of dealing with these kinds of problems. I look forward to what you may have to tell me, and I will relate what I learn as I go along.

ok, here we go!

The card is Dell P/N 8DTHW, and the cable is NK4P3.

There's discussion (and images showing the hardware in question) about these things here: ‎Dell DPWC500 8DTHW P1XY1 Thunderbolt 3 card with Precision T5820. Success??? | DELL Technologies, which is about a Precision 5820 (which I have, as well as a 7960); as I've said, the card worked in my 5820 without any cable - in fact, I don't think there's a motherboard connector in either the 5820/7820 anyway, so I'd say you don't need it.

As for the support given by Dell, I'd agree that it's pretty rubbish.  In my own quest for Thunderbolt 4 support in my 7960, I've been ping-ponged ad infinitum by Dell Sales and Dell Technical Support, but I won't give up, and like you, I'll report what happens to help other traumatized victims of the Dell support system.

@abz_t​ It's also worth noting that Thunderbolt-related BIOS settings only appear when a card is detected, so you can turn the support on/off via BIOS when the card is actually in-place.

Thank you for sharing that information. I think I need to just get the board and try it, without the GPIO cable, and see if it works. I'll report either way.

@abz_t​ That'll be useful for others that come searching for answers - rather than saying 'it works now', which is singularly useless :)

@johnnyboyc​ Just wanted to let you know that I am getting a P1XY1 card without a cable just to see if this can work. I am expecting it to arrive next week,

@abz_t​ Fingers crossed it works for you.

I received the P1XY1 after a fashion yesterday, because the US Postal Service routed it to my city, than sent it to a logistics center two hours away, got it back to a logistics center and distribution center in my city, and finally on

to me.

I installed the board in my T7920(no gpio cable), and after a fashion came to find out that there is no boot

support. Windows boots, shows the thunderbolt device in the device manager, worked properly with

a thunderbolt dock, and properly worked with a thunderbolt SSD.

The bios indicates that it can support thunderbolt, has an option to enable thunderbolt, documents that

there are options to enable thunderbolt booting- but none of these options for thunderbolt booting

appear such that they can be enabled.

One of the main reasons I got the T7920 had to do with wanting to be able to boot from thunderbolt

storage devices. Ah well.

Hope this is helpful and interesting.

One revision to clarify the previous message- booting into windows occurred usng a USB 3.1 interface to an external raid 1 drive that should also support thunderbolt. I also tried working with an SSD drive with a bootable windows system that will boot via thunderbolt on a Precision 7530 laptop but not on the T7920.

gah!  So nearly there but not quite.  I wonder if the addition of the GPIO cable would aid the booting of your external drive?

@johnnyboyc​ I wish I could test that possibility. The T7920 does not

have a connector on its motherboard for a GPIO cable.

Just to let you know- I purchased the official actually specified kit for the T7920:

https://www.dell.com/en-us/shop/pcie-thunderbolt-3-card-full-height/apd/540-bcxe/adapters

This included a board and a displayport interconnect cable. The board was a 083T0C, not the

P1XY1 I bought from ebay.

Even so, despite text in the 2.40.0 BIOS that gives mention to Thunderbolt Boot Support and Thunderbolt Boot modules, using this card did not make those options appear and nothing could be booted via Thunderbolt. My Thunderbolt dock did function correctly.