07-08-2019 01:06 AM
I have acquired a Thunderbolt 3 dock with 100 Watts power delivery to connect to my X1 Extreme.
I then ran a CPU benchmark to see how the notebook would handle the somewhat lower power supply compared to the standard 135 Watts power brick.
To my disappointment I noticed that the CPU frequency stayed very far below specifications during the benchmark.
Now I'm wondering why this is the case, since 100 Watts should have been enough to power a simple CPU benchmark without throttling, since GPU load was minimal.
How exactly does the notebook behave if it is provided with less than the recommended power? Is it specified somewhere?
07-08-2019 08:09 AM - edited 07-08-2019 10:21 AM
I'm confused by the 100W PSU. Are you sure you have the correct dock for the X1E1? There's been a lot of confusion about which dock works with the X1E1. There's only really 1 - the Thunderbolt 3 doc in the US -> Part # 40AN0230US --> https://www.lenovo.com/us/en/accessories-and-monitors/top-tech/Thunderbolt-WS-230W-dock-US/p/40AN023...
It comes with both a 65W and 230W PSU units and you must connect both of them to the correct slots. I think the 230W drives the X1E1 and the 65W drives the dock internals itself. I did some deep "which dock" diving before purchasing for an X1E1. This model works well with my setup. I have a single 4K monitor connected along with networking. I used a nicer BT speaker for the main desktop speaker seetup and that pairs with the X1E1.Nothing super complex.
Critical -> Be sure you update the dock's firmware as I read there were a lot of issues in older revs which have been fixed. You must connect the X1E1 to the TB3 with the unique double-connector cable which delivers power and logic.
Also be sure to update the X1E1 firmware and drivers to the latest using Lenovo Vantage. There are some newly released power, thermal fixes in there too. Bottom line, pushing the pCPUs a/or pGPUs on these units hard will result in some protection / throttling. There are quite a few threads on that too in the X1 forums but that's the price we pay for thiness and all this Xtreme power density! Peace.
07-08-2019 10:25 AM
I'm using the HP Thunderbolt dock G2, because I got it on the cheap.
It has a 120 Watts power brick, and claims to be able to deliver 100 Watts through the Thunderbolt port.
Everything works fine really (USB devices, monitors), however I hoped to have the notebook powered through the Thunderbolt port also, which doesn't seem feasible now with the strong throttling going on.
07-08-2019 10:42 AM - edited 07-08-2019 10:43 AM
The special 2 prong "docking cable" supplied with the TB3 dock mentioned above delivers power directly into the square power port and also connects the logic between the TB3 and X1E1. My gut says what you are attempting will not do what you want due to the power requirements of the X1E1 and the limits on the Thunderbolt ports. I think I read that somewhere on another X1E1 thread too.
Take a look at the UserGuide also in that link. Cheers.