logo

Live Production Software Forums


Welcome Guest! To enable all features please Login or Register.

Notification

Icon
Error

Options
Go to last post Go to first unread
ONV  
#1 Posted : Thursday, March 25, 2021 7:09:48 AM(UTC)
ONV

Rank: Newbie

Groups: Registered
Joined: 3/25/2021(UTC)
Posts: 1
Germany
Location: Hamburg

Hi there!

the TL;DR

What system components are most vital to run vMix in UHD mode, handling 2 (or more) 2160p video streams (via a HDMI capure card)?
I assume the graphics card, specifically the amount of VRAM is a major concern?

the long story

I'm running vMix (4K edition) in a mid-sized streaming studio downtown and we usually only do HD productions. It's a small PC featuring a Blackmagic Design 4x HDMI 2.0 input card, an Intel i7 8600K CPU +16 GB RAM and a GTX 1650 Super. So, it's a capable system but certainly nothing high-end.

Recently I used one of our A7sIII cameras for a UHD master shot. Camera HDMI out was set to 2160p, vMix was set to UHD, the external output remained at 1080p and so did the RTMP stream.

(I used that UHD master for cropping in and do virtual zooms with the "merge" transition btw).

GPU mem usage hovered around 68 % I think (the GTX1650 Super has 4GB of VRAM). The CPU didn't crack the thirties. Everything worked well!

Then I switched a second camera to 2160p HD and suddenly I had a craaazy delay in vMix! Audio was still good (very low lag) but the image lagged massively (felt like almost 2 seconds). GPU mem jumped to 90 % (I don't recall the CPU usage but it wasn't crazy high). Everything was still smooth but the lag was of course insane.

I do have an RTX 2080 Ti from my workstation at home laying around and we thought about throwing that into the vMix PC. Would that help? It has 11 GB of VRAM and a higher clock of course. (It's a bit of a hassle to open up and change the internals of our streaming PC for several reasons so I don't want to "just give it a try").

OR could it be something else?
OR is it generally just not a good idea (or "not feasible") to do this?

MANY THANKS!
Oliver



kross  
#2 Posted : Friday, March 26, 2021 5:59:57 AM(UTC)
kross

Rank: Advanced Member

Groups: Registered
Joined: 10/31/2020(UTC)
Posts: 67
United States

Was thanked: 12 time(s) in 12 post(s)
From your description it sounds like the GPU is the bottleneck. It certainly would be worth trying with the better GPU that you already have.
Users browsing this topic
Forum Jump  
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.