Display Lag

[Vingt-2]

What exactly is display lag and more importantly, how is it computed ?
I'm getting a variable amount of display lag on different games at same resolution. I'm pretty sure it's not related to some TV image processing delay as I never had such lag while directly plugged via HDMI to my GPU. Lowering the resolution also drops the display lag significantly (would make sense for TV processing as well as some latency inherent to the steam link decoding chip).

Has anyone managed to reduce display latency to < 50ms (1080p) ? My bitrate is ~25 Mbs and I have no input lag. I'm on WIFI 5GHZ and I am getting an average of say ~0.5% packet loss. I'm wired from PC to Router

[Tucu]

It is encoding + network + decoding.
The minimum I have seen is around 20-25ms for the software and Intel encoders at 1080p60. So less than 2 frames. With the AMD encoder I get between 40ms and 60ms for most games in its current implementation. The TV will likely add another 20-50ms of latency.

[Wally the Whiffopotamus]

I believe the listed display lag in this context doesn't include your TV's additional processing. You'd have been dealing with that regardless, so you can discount it for this question.

As Tucu noted, the listed number should include the time to encode a frame, send it via ethernet or wifi, then decode and display via the Link. If I'm playing a game at 1080p with Balanced settings, I get under 20ms of latency via wifi, which is acceptable. Changing to Beautiful bumps that to ~35+, which is noticeable and not ideal for twitchy games. This is all via Nvidia encoding (970) + software.

[Vingt-2]

Hi thanks,

Yeah I mainly asked how it was computed as I was reading pretty much everywhere that display lag was an effect of TV processing that you could turn off bla bla bla, and was very curious as how that measure was effectively acquired.

Wil try to switch down the bitrate (or select the balanced preset), although I doubt I'll be satisfied with the picture quality. Welp, I tried the steam link.

[henryg]

50ms is not great. If you change the resolution to 720p, I'm sure that you'll have much lower latency, but the resolution will be noticeably lower. You could also try 1600x900, which is an option in the Steam Link advanced client settings, and might be a good compromise.

If you have a fast and recent CPU, with 6 or more cores, I would also try turning off Hardware Encoding under the Advanced Streaming options. Software encoding is the highest picture quality and also the fastest encoder, if you have the CPU horsepower to spare.

[Quad]

I've said this in a few other threads but try turning off "Network packet priotitiazition".

On my network(s) it causes packet loss and a extra 20ms of lag with anything over 20 MBit/s.

[Vingt-2]

Originally posted by henryg:

50ms is not great. If you change the resolution to 720p, I'm sure that you'll have much lower latency, but the resolution will be noticeably lower. You could also try 1600x900, which is an option in the Steam Link advanced client settings, and might be a good compromise.

Sure dropping the resolution to 720p fixes the issue, but it's 2016 almost, who's okay gaming in 720p :p ?

I finally found the time to test a wired connection to my router, and I'm getting ~20ms in that setup. Seeing that I'm having ~max 1% packet drop in 5GHZ and only ~1.5-2ms of ping time, I'm having a hard time figuring out the maths between this 2-fold increase in latency.

Originally posted by henryg:

If you have a fast and recent CPU, with 6 or more cores, I would also try turning off Hardware Encoding under the Advanced Streaming options. .

That didn't help on a 4 cores (8 threads) i7 4790 from last year. Didn't make it worse either, so I might keep that for GPU intensive games.

So far I have managed to reduce to ~20ms by dropping the bitrate to a max of 20 Mb/s. The image quality takes a significant hit, but at least it's an acceptable amount of lag.

Henry, I wonder what kinds of performance you are getting at the office on an ideal setup, including wired and wireless ?
Also while you're around, do you mind me asking if you're planning on improving compatibility with the Playstation 4 controller (namely rumble, wake-on, and controller switcht-off features) ?