It Would Seem I've Been Deceived (GPU Encoding)

[ninbura]

I have always read and been told that the encoding chips on all 10 series GPUs were equal.

I have recently switched from a GTX 1080 to a GTX 1050 thinking I'd get the same encoding performance only to find that I am not whatsoever. With my 1080 I could see in task manager that I was using 23% of the available encoding while encoding a 3440x1440 @ 100FPS stream and a 1080p60 stream both streams at a 250M bit-rate simultaneously using FFmpeg. Now I go to test with my new 1050 and encoding only the 3440x1440 @ 100 FPS stream (all same settings) is using 65% of the encoder, and at one point jumped up and even dropped frames... this never happened with my 1080.

I would think this drastic change in performance would directly correlate with the VRAM given that that would be the "only" difference between encoding on a 1080 and a 1050 according to most things I've read, but the VRAM usage never got above 1GB...

Anybody know more about this stuff than me? Would switching to a GTX 1060 6GB get me back to similar performance I was seeing with my 1080? Really wish I would have just kept the dang thing...

I plan on encoding a 3440x1440 @ 100FPS stream and a 4K60 stream simultaneously.

[spartaman64]

https://developer.nvidia.com/video-encode-decode-gpu-support-matrix

apparently the higher end gpus have 2 nvenc chips and its the 6GB version of the 1060 and up i would guess

[ninbura]

12 minutes ago, spartaman64 said:

https://developer.nvidia.com/video-encode-decode-gpu-support-matrix

apparently the higher end gpus have 2 nvenc chips and its the 6GB version of the 1060 and up i would guess

Screw me....

I also found this - https://devtalk.nvidia.com/default/topic/987460/nvdec-cuda-nvenc-speed-comparison/

Implies that the 1080 has 2x the encoding even compared to a GTX 1070, but it seems like this chart you share indicates otherwise

Don't want to buy another GPU only to find I just need to get a 1080 again.

[xAcid9]

23 minutes ago, spartaman64 said:

https://developer.nvidia.com/video-encode-decode-gpu-support-matrix

apparently the higher end gpus have 2 nvenc chips and its the 6GB version of the 1060 and up i would guess

Which 1060 use GP104? 

[spartaman64]

7 minutes ago, xAcid9 said:

Which 1060 use GP104? 

the higher vram version

[ninbura]

Bit worried about that discussion I found saying the 1080 has 2x the encoding power in comparison to a GTX 1060 and even a GTX 1070.

If anyone knows more about this please chime in.

[xAcid9]

2 hours ago, spartaman64 said:

the higher vram version

No, 1060 6GB is full fledged GP106 and 3GB one is the cutdown. .

 

 

 

[DildorTheDecent]

2 hours ago, xAcid9 said:

Which 1060 use GP104? 

Either some weird OEM/Ti variant or maybe the GTX 1060 was re-released with a cut down 1070 GPU. 

[ninbura]

Well, I've dug about as deep as possible and the evidence seems conclusive.

 

If you want to encode two streams of 4K (or streams of similar bandwidth) at stupid high bit rates simultaneously you'll need a GTX 1080 or up. Some other cards do have two NVENC chips like the GTX 1080, but for one reason or another only one can be activated while anything upwards of the GTX 1080 gives you access to both chips which doubles encoding capabilities.

Another thing to consider is VRAM, while I knew encoding dipped into VRAM (which is why encoding can and does affect game performance) I didn't notice it would use close to or even sometimes above 1Gb per 4K stream when capturing high bit rates. Since the 1050 only has 2Gb that is another bottleneck stopping you from capturing two streams of 4k60 at high bit rates.

Lastly the GTX 1080 encodes much faster than its ten series brethren and is far less likely to fall behind. This explains why when encoding with the GTX 1050 I experienced encoding spikes which overflowed my buffer.

Moral of the story is do your own research before committing to anything, but to be fair I can't believe the amount of people who suggest all GPUs in any given series have the same encoding performance when the notion is completely false.

I'm off to buy another 1080, which sucks because I already had one but sold it, and it had a top notch EKWB block on it too. Luckily the universal block I purchased for my 1050 should work fine on it too although I will have to buy additional heatsinks to cover the additonal RAM and VRMs, nor will it perform or look quite as good.  After all is said and done I will have lost close to $100 through fees and re-buys while I was trying to make a quick buck.

Feelsbadman

[spartaman64]

9 hours ago, xAcid9 said:

No, 1060 6GB is full fledged GP106 and 3GB one is the cutdown. .

 

 

 

 

 

idk the chart from nvidia says 1060 - 1070 ti GP104 ¯\_(ツ)_/¯ might be a typo

[ninbura]

Got another GTX 1080 and got it setup again.

Encoding the exact same stream on the GTX 1080 is using 23% of the available encoding power, while the 1050 was using around 65%.

Not even a factor of 2:1, the GTX 1080 supposedly has 2 of the same NVENC chip that the 1050 has but there has to be more than that going on considering that it's 65% more efficient ((65-23) / 65 * 100).

Anyways, everything is working now, thought I'd update in-case someone else ran into this crap - be warned the encoding potential is not the same with all like series GPUs.