An external SSD that disconnects from a USB hub is usually short of power, and sometimes a power-saving setting turns the port off. A single SSD can draw close to 900 mA, which is the whole budget of a USB 3.x port, so a bus-powered hub that shares less power cannot keep it running. Other causes are a worn cable, an overloaded connection back to the computer, or a hub chained behind another hub. Work through the fixes in order, and back up your data first, because a drive that drops out mid-write can lose files.
Quick answer: An external SSD disconnects from a hub mainly because of low power or a sleep setting. Use a powered hub with its adapter connected, plug the SSD into a fast data port or the computer directly, turn off USB selective suspend on Windows, and swap the cable. If the SSD still drops out, test it without the hub. The Gitfos C1Pro is a powered hub that needs its 65W adapter.
Why an external SSD disconnects from a USB hub
Four causes account for most disconnects: low power, power saving, a shared connection, and a bad cable. Each symptom points to a likely cause.
| Symptom | Likely cause | Fix |
|---|---|---|
| Drive vanishes when a second device is plugged in | Hub power budget exhausted | Use a powered hub with its adapter connected |
| Drive vanishes after sitting idle | Windows USB selective suspend | Turn the setting off |
| Drive drops during a large copy | Overloaded connection or weak power | Move other devices off the hub |
| Drive works directly but not on the hub | Hub chain, cable, or port | Remove extra hubs, swap the cable |
The power numbers behind this are in Evetech's guide: a USB 3.x port supplies 900 mA at 5V, which is 4.5W.
Fix an external SSD that disconnects: step by step
Start with the cheapest checks and move to hardware changes last.
- Back up the drive's data to another disk.
- Plug the SSD straight into the computer. If it stays connected, the hub or its power is the problem.
- Connect the hub's power adapter and use only a powered hub.
- Move other devices off the hub, especially phones that are charging.
- Try another cable and another port on the hub.
- Remove any second hub from the chain.
- On Windows, turn off USB selective suspend.
Turn off USB selective suspend on Windows
Windows can switch off a USB port to save power, and an idle SSD may then drop out. DriveSavers lists the steps.
- Open Control Panel, then System and Security, then Power Options.
- Click Change plan settings, then Change advanced power settings.
- Expand USB settings and select USB selective suspend setting.
- Change it from Enabled to Disabled and click Apply.
On a Mac, the Energy Saver options are more limited.
Where to plug an SSD into the Gitfos C1Pro
Plug the SSD into one of the C1Pro's 10 Gbps ports and keep the 65W adapter connected. The hub has two USB-C data ports and one USB-A port at 10 Gbps, and four USB-A ports at 5 Gbps. Connect the hub to your computer with the included full-function USB-C cable.
| Port | Qty | Spec |
|---|---|---|
| USB-C data | 2 | USB 3.2, 10 Gbps |
| USB-A data | 1 | USB 3.2, 10 Gbps |
| USB-A data | 4 | USB 3.0, 5 Gbps |
| USB-A data or charging | 2 | 5 Gbps data or 7.5W charging |
What these fixes do not solve
No setting fixes a drive that is failing or a hub that is running past its limits.
- The C1Pro needs its 65W DC adapter connected. It has no bus-powered mode.
- All ports share one 10 Gbps connection to the computer, so two fast SSDs used at the same time will not each reach 10 Gbps.
- The USB ports on the C1Pro do not output video. Only the HDMI port does.
- A faulty drive or a bad cable can look like a hub problem, so test the drive without the hub.
- Gitfos has not published sustained-write tests for SSDs on the C1Pro, so treat the port speeds as maximums.
Frequently asked questions
Most disconnects come down to power first and settings second.
Why does my external SSD keep disconnecting from my USB hub?
The most common cause is not enough power. A single SSD can draw close to 900 mA, which is a whole USB 3.x port's budget, and a bus-powered hub shares far less. Windows power saving can also switch the port off.
How do I stop Windows from turning off my USB drive?
Open Control Panel, then Power Options, then Change plan settings, then Change advanced power settings. Expand USB settings, set USB selective suspend setting to Disabled, and click Apply.
Will a powered USB hub fix an SSD that disconnects?
Often yes, if low power is the cause. A powered hub has its own adapter, so each port gets a steady supply. It will not fix a faulty cable, a sleep setting, or an overloaded connection to the computer.
Can I lose data when an SSD disconnects?
Yes. If power runs out while the drive is writing, files can be damaged or lost. Back up your data before testing fixes, and use safe eject before unplugging.
Does daisy chaining hubs make an SSD disconnect?
It can. Each extra hub shares the same power budget and the same connection to the computer, and adds a small delay. Plug the SSD into the computer or the first powered hub.
Next steps
Test the SSD on the computer first, then add the powered hub back. To understand the power side, read do I need a powered USB hub, and to check hub chains, read can you daisy chain USB hubs. For port speeds, see USB 3.2 Gen 2 vs Gen 1. For a powered hub with 10 Gbps ports, see the Gitfos C1Pro, browse more hubs and charging options, or reach the team through the support center. More fixes live in the Support blog.