Question Issues extending USB 3 port on PC


Aug 12, 2018
This has been the bane of my life!

I'd really appreciate it if you could shed some light on this whether it's because I'm using the wrong items or I have a driver issue.
I can't see any issues with drivers or incorrect cables so I'm just stumped.

My PC is under the stairs in the hallway. I have a video cable and two USB cables running about 2.5 metres from my PC into a wall outlet in my living room. I use one USB port for my wireless mouse & keyboard. The other USB port is to transfer data from either flash drives or self-powered external storage drives. I don't have an issue using the mouse & keyboard no matter the setup.

With data transfers I get I/O errors, sporadic disconnections or the drive simply not appearing in Windows Explorer.

I'm using USB 3.0 Wall port connectors that connects to the USB 3.0 three metre extension cables that connect to the PC. I have tried so many combinations such as omitting the wall ports and trying different cables including adding a dual power Y adaptor cable because I thought it might be a lack of power. I have also tried the setup using a different PC, all with similar results. I tried them in a different area of the house just in case interference was the issue.

I don't have any problems when I plug an external drive or flash drive directly into one of the USB 3 ports on the PC, no errors and at full speed. It's when I add the extensions cables that the issues arise.

Here are the components I have tried either separately or in combination. I will say that when using the dual power Y adaptor cable I don't think I get any errors or disconnections BUT only at USB 2.0 speed.

Dual Power Y Adaptor Cable
USB 3.0 Three Metre Extension Cable
USB 3.0 A Wall Socket Plate
USB 3.0 Three Metre Active Repeater Cable

Thanks very much and really hope you can save me from getting up from my chair, pulling the panel away from the stairs every time I want to insert a drive or phone to my PC!


The issue IMHO can and will be the length of the cables. In fact, you will need premium grade high bandwidth cables if you want to have successful data transfers, which isn't cheap. To add, what is the length of wire in your walls? Might I ask why you've resorted to having the system under the stairs? You should ideally have it next to at arms length away, unless you're working with a server that has all fans blasting at full speed.

Speaking of servers, you forgot to include the specs to your system. Please include your system's specs like so:


According to a Wikipedia article on this, the USB 3 standards do not specify a max cable length; they only specify the cable must meet some standards for cable quality. It also says the practical length limit appears to be 3 m, and I see that is what you are using. So that leaves us with the possibility that the cable you are using at the "limit" of length is not quite as high-quality as it needs to be. Add to that the fact that you also have an extra connector (from cable to wall socket) involved. The problem MIGHT be light wiring in the cable leading to signal loss, OR it might be inadequate shielding in the cable from external noise signals. The USB 3 system anticipates noise contamination to be an issue and has components and data coding devices to detect and correct for those problems, but they are limited in what they can handle. So MAYBE a better cable would help. Also make SURE that, at the computer end, there is a connection to a good reliable Ground for the entire system, as well as a good Ground shield connection of the cable to the socket on the computer. This computer system Ground is not just for electrical fault protection; it is important to allow easy diversion of noise to Ground, thus reducing noise in the cable signal wires.

You might consider this also, if you have not already. The wall outlet fixture you show should really be mounted in a metal box in the wall, with the Ground connections of the socket and cable also in contact with that box. That would provide a closed metal containment of all the exposed wires of the connectors at that location, reducing possible noise pick-up there.

Note that I am NOT recommending a direct extra Ground connection to the wall outlet fixture and/or its mounting box. The cable already should have a good connection to Ground at the computer end. Adding a different Ground lead at the other end of that cable can create a "Ground Loop" situation that makes matters worse.


Aug 12, 2018
Thanks for your replies and help.

This is frustrating. These cables are sold as being able to support flawless USB 3.0 speeds so could it be they're not fit for purpose? As stated, I have tried them in different environments and excluded the wall plate in some tests. The best result was including the Y adaptor for extra power but transfer speeds were around USB 2.0. Every cable or device is linked above. Can you recommend any 'premium' cables?

I put my PC under the stairs during my bright idea moment when I bought my house 5 years ago. It was almost an empty shell so I laid CAT6 cable all over the house under the floorboards and had ports connecting to each for devices such as HDMI over CAT and the data network side running down into a cupboard next to the stairs. I wanted everything out of sight and tidy. Never really used most of the stuff in the end and technology has moved on.

Also, I didn't want any fan noises even though I have a waterblock on my CPU and the PSU is fanless! I had a waterblock on my GPU too but since replacing the outdated card with a better but budget one , buying a new one is just too expensive. You can hear the faint hum of the pump. I don't even have a proper case as it's an open one for testing. I'm not into gaming as much now so I might move it into the living room if I can make it silent without spending (new year resolution!) too much. I can see water cooling has really moved on with all these straight rigid tubes among other cool stuff. All this might be an alternative to fixing the underlying issue!

My specs are:

CPU: i5-4460 CPU @ 3.20GHz
Motherboard: Asus H81M-C
Ram: 8127GB (1600MHz)
SSD/HDD: Crucial CT240M500SSD1 (223GB) / WDC WD30EFRX-68AX9N0 (2794GB)
GPU: Geforce GTX 1050i
PSU: Seasonic Fanless 520W 80 Plus Platinum Silent Modular
Case: LIANLI ATX Case Black PC-T60B
OS: Windows 10 Pro

Thanks again.