Hi there,
I’m sure, I’m not the only one who still knows about spinning disc memory devices Also this might be a very rare issue.
I’ve got a Pioneer BDR-XD07U USB Blu-ray Drive, which is rated at 5V DC and 1A. Whenever a disc starts to spin up the drive resets and begins detecting the disc anew. I tried an USB A on the left side and an USB C on the right side, slots 3 and 6.
In slots 4 and 5 of my FW16 are also one USB C and one USB A, here the drive works as intended. Since I put the DP and HDMI modules in slots 1 and 2, I didn’t test these, but as all four of them are capable of charging the laptop, I think these are also the ones giving out enough power for power hungry devices, such as external disc drives.
This is meant as a FYI post, not a complaint or feature request.
I have power related problems with attaching a SN850X nvme in USB enclosure to Slots 3/6. It keeps cycling power every few seconds, but the enclosure works ok on slots 1,2,5,6.
I think it is supposed to work in slots 3.6 as they are USB 3.2, but there is probably a BIOS/EC bug that needs fixing.
Yes, I’ve also encountered a few NVME as well as 2,5" enclosures with SSDs inside, which draw too much power to be functioning correctly. There might even be some older, high-speed USB thumb drives, which maybe won’t run on these two ports, 3 and 6.
Also noticed powering an arduino off the usb ports 3 & 6 results in brownouts whereas it works fine in any other notebooks USB-A ports I have.
Moving the ports to anything else resolves it.
Hi, I got this from FW support today (quote slightly edited by me for clarity).
" Ports 3/6 (as outlined here) are with lower power supply 0.9A@5V, which is 4.5W. All the rest ports should be good, 3A @ 5V which is 15W."
So this confirms the probable reason for the DVD/BD drive not working in Slots 3/6.
It also explains why my NVME SN850X, inside a USB enclosure, does not work in Slot 3/6.
For example, SN850X needs 3.3V DC and 2.8A = 9.24W (over PCIe bus), so one needs a USB port that can output more than 9.24W for it to work, so that should work in a 15W USB port, but it would not work in a 4.5W USB port.
The Pioneer BDR-XD07U USB Blu-ray Drive, which is rated at 5V DC and 1A. It is 5W which is just over the 4.5W for the USB port 3,6.
Maybe @Matt_Hartley could ask the support department to update the graphic on this FW16 Expansion Card Graphic to put an * [asterisk] by the (3) and (6) slots to indicate limited output of 4.5W MAX?
Might not be a bad idea to indicate the MAX output power of the other ports at 15W ea. and if there is a total wattage limitation from the ports (either by side or as a whole) the laptop can put out. Invariably, someone is going to try and hexapus? (play on octopus) their machine to drive something from every slot.
I know 0.9A sounds close to 1.0A; however this is a laptop whose design is to try and maximize portability/longevity without external power sources. I understand the reasoning to limit it to 4.5W; others may not understand how big a deal an extra 0.5W for each port.
[Full disclosure, I have been thinking in my head USB 3.0 was at least 5W of power for decades! Where is the double facepalm emoji? Thank you @JP3692 !]
Every little bit helps when trying to optimize a lower power setup.
It is a shame the power chips that supply the 5V, 0.9A don’t result is a log message when an attached device tries to draw too much power from the port.
At the moment, there is no log message, so one has no idea as to why a USB device is failing to work, or working unreliably.
For example, there are some reports of NVME enclosures working for a bit and then failing/brownout when a user tries to use the device more, resulting in the device finally drawing too much power from the port.
From reading the specs of my SN850X, it has a feature whereby one can limit it to only using 4.5W of power, but currently the util that programms that can only do it over an NVME M.2 interface, and not via the USB enclosure.
I think it would be good if one could reach a point where one plugs a device into the USB port, and then send the device a command that limits its power draw to 4.5W if it is placed in a USB port that can only supply 4.5W. Thus resulting in a working device in that USB port, even if the device might be slower as a result, at least it would work.
Also this might be a very rare issue.
to put an * [asterisk] by the (3) and (6) slots to indicate limited output of 4.5W MAX? 
I understand the reasoning to limit it to 4.5W; others may not understand how big a deal an extra 0.5W for each port.
