T480s sensitivity to USB power surges

[dandreye]

Hi All,

I have two similar portable Hitachi Touro 1TB Mobile drives, each with a micro USB3 port. One of them has a 7200rpm HGST disk inside and the other a 5400rpm one. When I plug the former one into any of the two USB-A ports of my "new" T480s laptop (running W11x64 in case it matters) the D: disk starts frequently disappearing (accompanied by error messages saying something like "The disk is not present") and reappearing next to C: with a typical sound as would typically be seen with a faulty USB port. When however I plug the latter one using the same USB cable there's no such issue with either port. Meanwhile they both behave perfectly fine when connected to an X1C9 that I have here too (also running W11x64). Could T480s be less tolerant to USB power surges than X1C9 by chance? I suspect that being a higher rpm drive the 7200rpm one occasionally pulls more than the 5400rpm one, and that happens to exceed some T480s tolerance limit. Wondering if anyone's seen such behaviour with their T480s or perhaps other ThinkPad models. Here's a video illustrating mine:
https://drive.google.com/file/d/1zodBIe ... sp=sharing

Also just noticed that the 7200rpm one works fine with the T480s when connected via USB voltage/ammeter, which doesn't seem to have USB3 contacts - only USB2 (data transfer rate maxes out at ~40MB/s vs ~130MB/s with a direct connection):
https://www.aliexpress.com/item/1005003218632489.html

And also the 5400rpm one develops a lot higher data transfer rate when it's connected to the X1C9 rather than the T480s, as if it's using USB3 with the former one and USB2 with the latter one.

Btw the 7200rpm one pulls up to 0.93A at start while the 5400 one does up to 0.80A. Not that much of a difference and they're both below 1A anyway...

Thanks in advance!

[axur-delmeria]

IIRC, according to specs USB 3.0 ports have 900mA max current (I don't know if it's been revised in later versions of the spec. That 7200 RPM external hard drive is technically out-of-spec.

[dandreye]

IIRC, according to specs USB 3.0 ports have 900mA max current (I don't know if it's been revised in later versions of the spec. That 7200 RPM external hard drive is technically out-of-spec.

Well spotted - thank you: the very first Google search result suggests it's still there:
https://tripplite.eaton.com/products/usb-charging

Meanwhile I decided to measure USB speed by putting an SSD instead of the 5400rpm HDD into its Hitachi Touro enclosure. The results are:
- T480s: 38MB/s read and 31MB/s write
- X1C9: 228MB/s read and 85MB/s write
, so the "5400rpm enclosure" itself can clearly go above the USB2 speeds. But then I tested both T480s ports with a different external SSD (NVMe) and this time got 450-480MB/s read and write speeds, so looks like the USB3 speeds are there. Does anyone have any thoughts why these Hitachi enclosures could be so unhappy with the T480s? (the "7200rpm one" disconnecting and reconnecting all the time and the "5400 one" working at the USB2 speeds despite it's clearly capable of USB3)

[axur-delmeria]

Have you tested other USB 3.0 devices and check their read speeds? There might be a hardware issue with your T480s; that, or some kind of odd configuration error. I dunno if there's a BIOS setting somewhere. You could also try booting from a Linux live USB then testing the read/write speed there, to check if it's a Windows-only problem.

[dandreye]

The only other USB3 device that I managed to get hold of so far is that miniature drive with an M2 (supposedly NVMe) SSD inside. It didn't flap even once and gave me clearly USB3 speeds ~450-480MB/s. Had to use a different USB cable with it though, as it's got a USB-C jack and not micro USB3.

[axur-delmeria]

You could try changing the cable, or get one of those Y-cables with an extra USB-A plug so it can get more amps from another USB port.

[dandreye]

Good point on the Y-cable: I might even have one of those lying around. For now I've ordered a micro USB3 to USB-C one to test those drives with the T480s's higher power USB-C ports.
But even the cable that I used with them has always worked perfectly fine with X1C9.

Update: the drive in question works fine at USB3 speeds of ~130MB/s with the T480s when using the following new cables that have just turned up:
- USB3-A to microUSB3-B
- USB-C to microUSB3-B

Also before the new cables turned up even the "5400rpm" drive started misbehaving with the cable in question, so from then on I only connected them both via the USB2 volt/ammeter.

My only guess now is that the X1C9's USB3-A ports are slightly different mechanically from the T480s's ones, so when my old cable (btw a genuine WD one) is plugged into the latter one it doesn't come into a reliable contact with some of its USB3 contacts, and putting the USB2 volt/ammeter in between to prevent passing USB3 circuits on "fixes" the issue.