# How can i use a Surface Pro 3 as a secondary monitor with my gaming laptop?



## Space Lynx (Jan 16, 2019)

basically want to use a surface pro 3 as a second monitor for productivity --- laptop is a gtx 1070, bought a mini DP port to HDMI, plugged mini DP into Surface Pro 3 and HDMI into laptop... doesn't work... any other thoughts?


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## RCoon (Jan 16, 2019)

Followed this guide?

https://surfacetip.com/use-your-surface-as-a-portable-display/


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## Space Lynx (Jan 16, 2019)

RCoon said:


> Followed this guide?
> 
> https://surfacetip.com/use-your-surface-as-a-portable-display/



Yes, I tried that method and found it very laggy and not well-refinded. I'd much rather use a cable setup, which I know is possible but just am not quite sure what cord I need. I have a Surface Pro 3 and a docking station which supports external monitors

edit: i think i figured it out, i need to buy a mini DP to mini DP cable. my bad.


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## Valantar (Jan 17, 2019)

lynx29 said:


> Yes, I tried that method and found it very laggy and not well-refinded. I'd much rather use a cable setup, which I know is possible but just am not quite sure what cord I need. I have a Surface Pro 3 and a docking station which supports external monitors
> 
> edit: i think i figured it out, i need to buy a mini DP to mini DP cable. my bad.


No. A display output is not a display input - connecting a cable between your other PC and your surface will do nothing at all. The SP3 (and most other PCs) lacks the hardware necessary for the display outputs to function as inputs. Apps or network-based solutions are the only option. Anyone telling you anything else is mistaken or misleading you.


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## Space Lynx (Jan 17, 2019)

Valantar said:


> No. A display output is not a display input - connecting a cable between your other PC and your surface will do nothing at all. The SP3 (and most other PCs) lacks the hardware necessary for the display outputs to function as inputs. Apps or network-based solutions are the only option. Anyone telling you anything else is mistaken or misleading you.




but i have a docking station for the surface pro 3. so it actually should work mini DP to mini DP


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## Valantar (Jan 17, 2019)

lynx29 said:


> but i have a docking station for the surface pro 3. so it actually should work mini DP to mini DP


Doesn't matter. The docking station doesn't magically give it a video input - quite the opposite, it likely gives it more outputs. You're still lacking necessary hardware for anything to work as an input.


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## Space Lynx (Jan 17, 2019)

Valantar said:


> Doesn't matter. The docking station doesn't magically give it a video input - quite the opposite, it likely gives it more outputs. You're still lacking necessary hardware for anything to work as an input.



can you tell me how to do it then? do i use ethernet cable? or does it have to be the laggy wifi method mentioned in post 2?


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## insane 360 (Jan 17, 2019)

what he is saying is the surface pro 3 can't become a monitor, only screen mirroring over wireless is your only option.  the internal connections for the mini dp only work as outputs not inputs


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## newtekie1 (Jan 17, 2019)

lynx29 said:


> can you tell me how to do it then? do i use ethernet cable? or does it have to be the laggy wifi method mentioned in post 2?



WiFi is the only option to do what you want.

Upgrading your WiFi to allow faster connections might make it less laggy.


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## Valantar (Jan 17, 2019)

lynx29 said:


> can you tell me how to do it then? do i use ethernet cable? or does it have to be the laggy wifi method mentioned in post 2?


Apps or services that allow it to function as a secondary display over WiFi is the only cheap and easy solution - and lag is unavoidable, as the video signal not only has to pass through at least one, possibly two wireless signals (source -> router -> SP3), but also has to be compressed at the source and decompressed on the SP3. Every additional step introduces more lag, and WiFi is notoriously unstable and sensitive to interference.

Something that _might _allow you to do this with less lag and compression is to use a USB capture device. I just tested my Elgato HD60s, and when connected to my desktop I can extend its desktop to my laptop's display by using Elgato's capture utilities (without actually recording anything). Lag was perfectly acceptable, couldn't see any perceptible lag when typing on the secondary display - but then the HD60s is advertised as giving "instant capture previews", so that's part of what it's made for. Of course, this is a costly solution - the HD60s is $180 on Newegg, and the cheapest thing I can imagine working with the full resolution of the SP3, the Cam Link 4K, is $130.

It's also worth noting that just displaying a static, empty desktop at 1080p60 on my laptop from the HD60s represents a ~20% CPU load and a ~20% GPU load on my laptop's i7-8650U in the standard capture utility that AFAIK only supports up to 1080p60. In the 4k capture utility, GPU load for the same stream hit 70% for some reason. A Surface Pro 3 might struggle with resolutions matching its native resolution, in other words.


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