Computer on another floor, 2021 edition.

March 6, 2021 7:05 PM

I'd like to use a monitor, keyboard, and mouse in my basement, but the computer itself is on the first floor. Can USB-C / USB 3 or another modern tech make this happen?

I know that I can plug my work laptop into a single USB-C dock like this and it will run a USB keyboard, a USB mouse, and a HDMI monitor. I also think I've seen some powered USB-C cables that claim they'll allow you to run a USB hundreds of feet instead of the 9-ish feet that's normally recommended.

So in theory I should be able to buy a powered USB cable, connect it to the PC tower, and run it down to my basement where a dock would connect to keyboard, mouse, and monitor — right? I'm willing to spend the money to try it out if it should work in theory, even if there are reasons it might not work in practice. This is for gaming so hopefully the latency would be minimal.

(Why not move the PC? Because I mostly use it where it currently is, so it's not worth moving it downstairs and upstairs again when I want to use it in the basement.)

posted by Tehhund to Computers & Internet (14 answers total)

The HDMI output over USB-C is part of an optional extension called Alt-Mode, which allows non-USB data (like HDMI) to also be carried on the cable. So, even if you have a powered cable or repeaters or something that supports longer runs it won't necessarily also carry the HDMI for your monitor. If you want to try it, be sure to confirm that the alt-mode video signal will also be carried over the full cable length.

According to this vendor, you might need to get a USB-C dock and a KVM extender and then connect them over ethernet to do what you want (which will introduce latency that might be a deal-breaker depending what sort of gaming you do).

Another possibility would be to get a USB extender for keyboard/mouse and a seperate HDMI extender for video, though that'll probably require running 2 pieces of ethernet downstairs (one each for the USB and the HDMI, I'm pretty sure the HDMI extenders require exclusive use of the ethernet cable).
posted by russm at 7:36 PM on March 6, 2021 [1 favorite]

Personally, I'd get a cheap computer for basement, and "remote control" (VNC, et al) the main computer if you need to access it.
posted by kschang at 8:17 PM on March 6, 2021 [14 favorites]

You didn't say how long of a cable run would be necessary, which is kind of an important detail.

"USB-C" is a type of connector. If you are running a cable to a dock with a USB-C cable, you are really talking about getting a Thunderbolt 3 cable. The theoretical limit on a fiber optic TB3 cable is 100 meters. Also, Thunderbolt 3 cables are very expensive and no one makes them anywhere near that long.

Up until recently it was pretty much impossible to get TB3 cables of any length measured in meters, although fortunately for you B&H sells a 25 meter fiber optic Thunder Bolt 3 cable in USB-C connectors. Unfortunately, it's $750.

If 50' is long enough I'd do that with HDMI and use Bluetooth 5 mouse/keyboard. Would be a lot cheaper.
posted by bradbane at 8:31 PM on March 6, 2021 [1 favorite]

I've faced a similar situation before, in a two-storey townhouse. I just ran a 10 metre HDMI cable from my PC upstairs to my TV in my living room downstairs, and used a Logitech wireless keyboard with touchpad (the kind that uses the Logitech unifying receiver, not bluetooth) to control the PC from my sofa. It was ugly but worked fine for me. Your mileage may vary depending on the distance you're trying to cover. I think HDMI cables get a little dicey over longer distances - I think I once tried a 20 metre HDMI cable and it just didn't work.
posted by yours in calendrical heresy at 8:37 PM on March 6, 2021 [1 favorite]

VNC or similar remote control tools will introduce significant latency, which I suspect will be a problem for gaming (depending on the type of games, of course).

If you are running a cable to a dock with a USB-C cable, you are really talking about getting a Thunderbolt 3 cable.

This isn't correct - USB 3 docks with USB-C connectors and video out but no Thunderbolt support are a thing, transporting the video signal over the USB-C altmode rather than over the Thunderbolt data link. Eg: this USB cable that will drive a display on a USB (not Thunderbolt) dock, vs. this Thunderbolt 3 cable, shorter and more expensive, that's needed for a Thunderbolt dock. Both have USB-C connectors on each end, but the Thunderbolt cable will carry data 4 times as fast. Note the Thunderbolt cable has the little lightningbolt icon and a "3", while the USB-only cable doesn't.

USB-C is a nightmare, where you have to look for the specific icons on the cable ends (that may or may not even actually be there) to know if a particular cable will work in a particular job, even though they all have identical-looking plugs.
posted by russm at 9:15 PM on March 6, 2021 [2 favorites]

I use Moonlight/Gamestream to stream games from my pc to the lounge over ethernet to an nvidia shield and it works great. If you have a streaming box then this type of setup would work well.
posted by onya at 9:37 PM on March 6, 2021 [2 favorites]

For the keyboard and mouse standard USB can do, using an extender if necessary. I also know of a wireless USB extender: a 4-port USB hub linked to a transceiver dongle in the computer, IIRC it is (or was) made by Belkin. But anything wireless, including using Bluetooth keyboard and mouse may or may not work, or not work reliably, between floors depending on the construction and distance. Native USB extenders can be 5m/15ft max, though you can use a few in series; for longer distances there are converters to run USB over a CAT5 network cable.

For video there are similar extenders, using one or more CAT5/6 cables between the computer and screen. They should obviously match the video interface used, and this plus the required distance dictate what you need to get. This is clearly more cabling hassle than USB-C, but as Russm already notes, there's high wizardry involved in getting the right cables and hubs; older tech is by now extremely mundane and cheap.
posted by Stoneshop at 2:06 AM on March 7, 2021

Though it's been discontinued for a while, the Steam Link box does this really well, provided it's connected over weird ethernet. Very low latency for gaming (plus support for controllers) and you can drop to the desktop and just use it as a very fast remote desktop kinda thing. Steam still supports it, and you can find them on eBay pretty easily for $20 or thereabouts.
posted by transitional procedures at 3:53 AM on March 7, 2021

(FWIW Steam Link is also available as an app that can run directly on sufficiently smart TVs, or android devices, or an RPi if you have one lying around)
posted by russm at 5:59 AM on March 7, 2021

Best answer: I've done essentially all of the things described in this thread for the same situation:

* 50 foot HDMI cable ($20) and a 50 foot USB cable (male-to-female, $20) + hub works the best. Effectively no latency, everything works normally because it's just another set on inputs and monitor. Long distance wireless mouse/keyboard didn't work well for me.

* Steam Link (hardware) - easiest alternative for gaming, if you already have ethernet at your remote location. Once connected, you can minimize Steam and run non-game apps. Adds a little latency and video encoding artifacts, but it's surprisingly playable for most games. Obviously not ideal for twitchy shooters and competitive gaming though.

* Steam Link (hardware via WiFi or software) - same situation, just more latency and lower quality video stream.
* Moonlight - assuming you have an Nvidia GPU, essentially the same as Stream Link for latency and artifacts, but controller support is more robust in Stream Link. Also possible to stream the desktop, not just individual games.

* Google Remote Desktop - useful for non-gaming situations, but way too much latency.
posted by hankscorpio83 at 6:22 AM on March 7, 2021 [2 favorites]

If you have an Nvidia GPU, Gamestream works pretty well. I haven't played a game on my PC's monitor in like four years now, it's all Gamestream for me. The Moonlight client will run on any Android/Android TV box. I find it works better than Steam Link, FWIW, but Steam Link works regardless of what GPU you've got.
posted by wierdo at 8:08 AM on March 7, 2021

I did this with a 75 foot run from my computer to an alternate monitor + kb/mouse.

The tech was a little different back in 2009, so I used DVI-Cat6 converters, USB-Cat6 converters, and optical fiber for audio. I got a good bit of visual noise on the video when my bathroom fan was on, so I ran some 3/4" metal conduit for 20 feet in a joist bay, and grounded it, which totally fixed it.

At some point I upgraded to straight HDMI and it worked just fine. I think with a long HDMI cable and a super long USB cable designed for boosting over that length you'll be set. I wouldn't mess around with docks or remote desktop-ing.
posted by MonsieurBon at 8:49 AM on March 7, 2021

Best answer: Active fiber HDMI cables capable of 4k/60 signals up to 328ft are pretty cheap these days, and coupled with an active USB extension, you can move the peripherals there as well. If it's just keyboard and mouse for peripherals, you can get USB 2.0 extensions up to 83ft. USB 1 over Cat-5/6 is also a thing, again for low-data-rate peripherals only, but up to 150' and quite cheap. USB-3 active extension cables exist also, if you really need USB-3 data rates for the peripherals you are moving.
posted by tomierna at 7:35 AM on March 8, 2021 [1 favorite]

Response by poster: Update: I already had a 50 ft HDMI cable lying around so I bought a 50 ft USB extension cable and ran both of them downstairs. Everything works, I can play games in the basement while the computer is on the first floor.
posted by Tehhund at 7:00 AM on March 30, 2021 [1 favorite]