Bug Report OBS disabling Crossfire?

Okay so I am running a system with two 6870's in Crossfire, this works perfectly fine at all times. However, when I use OBS I was noticing a much lower frame rate than I should be even with streaming factored in so I decided to investigate with MSI Afterburner. Turns out that when I stream with OBS it disables my Crossfire, not the actual setting for Crossfire but it for some reason forces all load onto a single GPU and makes zero use of my other one costing me considerable performance.

Is there any particular reason this software should be doing that? Does OBS actually allow you to stream in fullscreen or is it just making it a borderless window giving you the illusion of fullscreen? That is all I can think of considering Crossfire does not work unless actually in fullscreen...

Some information on this would be greatly appreciated, thank you.

I was unaware that OBS forced Crossfire to off, but this is actually for your own good if you intend to use the application, since the capture methods used do not work with multiple GPU setups.

OBS does not force anything into borderless windowed mode, but it may be so that it actually turns off Crossfire, since this is essential to game capture and in some cases software capture working properly. Also, this does not belong in bug reports.

paibox said:

I was unaware that OBS forced Crossfire to off, but this is actually for your own good if you intend to use the application, since the capture methods used do not work with multiple GPU setups.

OBS does not force anything into borderless windowed mode, but it may be so that it actually turns off Crossfire, since this is essential to game capture and in some cases software capture working properly. Also, this does not belong in bug reports.

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Well I would like to know if there is a way to stop this from happening, the only reason I started using this software was because I no longer wanted to pay for Xsplit and that had no issues with my Crossfire running so...

I'm pretty sure this belongs in this section according to the description of the section.

Post here if you're having any trouble with OBS, whether it's an error, a crash or any other problem.

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I'd say this is a problem.

Alright, the description does match up, so I'll give.

Does this happen with older versions of OBS, or did it only start happening recently? It is entirely possible that a recent version has made it enable a profile where Crossfire is disabled, since many people have had issues with both Crossfire, SLI and laptop setups with multiple GPUs.

Jim (the main developer) is currently asleep, but if you drop by the chat, whether using the web chat or an IRC client, he can most likely help you out. For now, I suggest checking your Crossfire profiles in the Catalyst Control Center or wherever they are these days, and if that doesn't help, temporarily downgrade to an older version that does not force Crossfire off.

This is actually the first version of the software I have used, I will look into an older build and if that does not change anything I will try and get a hold of Jim as soon as I can, thank you.

Just keep in mind Crossfire/SLI do not play nice with streaming, especially if you need to use game capture on fullscreen games (in fact, most games flat out will not capture properly with Crossfire/SLI enabled as far as I know)

I was unable to find any older builds of this software, still looking for some kind of solution.

I'm not quite sure what you mean, all older versions are available on SourceForge in pretty much the same place as the main download, here: http://sourceforge.net/projects/obsproject/files

As for as solution, I'm not sure you're going to find one. OBS is currently designed in a way that can not work with multiple video cards, unless using an intermediate rendering manager such as the desktop window manager in Windows, and if what you say is correct, Crossfire doesn't work in windowed mode anyway?

OBS shouldn't be disabling crossfire, I didn't put any code that does that.

Jim said:

OBS shouldn't be disabling crossfire, I didn't put any code that does that.

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That is very odd then lol, the second I hit my hotkey to start the stream the usage on GPU #1 tanks to 0% and the other one tops out at 99% usage, interesting.

It could be doing that by itself. To efficiently capture it requires sharing GPU memory, so it could be determining this on its own. Just a guess, though.

I can confirm that OBS does not disable crossfire. I currently stream with dual 7870's and previously streamed on dual 6870's. What catalyst build are you running?

Ok, after stating no issues I am experiencing this problem while streaming Bioshock Infinite. Start the game, crossfire works normally but as soon as I hit the button to stream it disables gpu 2.

Just wanted to update that this is still a persisting issue taking place.

I'm sure Jim can fix that. Like a "SLI/CFX?" checkbox in the video settings for enabling a "special" code for multi-GPUs.

WayZHC said:

I'm sure Jim can fix that. Like a "SLI/CFX?" checkbox in the video settings for enabling a "special" code for multi-GPUs.

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I really hope so for my sake and others like me with mid-range GPU's. If I had two 7970's or something it using one card wouldn't be a big deal because my performance would still be very high but with just one 6870 being utilized the results are discouraging.

Also cfx setup works only in fullscreen mode. Cfx doesn't work in Windowed mode. Not sure about SLI but afaik Cfx doesn't work in windowed mode.

These are the situations why i always prefer one high-end gpu over two mid-range gpus with same price tag (total price). Two mid-range cards might be more powerful compared to the one high-end by 5-10% but imo one card is always better choise.

Next time i upgrade my gpu (lets say summer 2014) i'll have two options:
1. Buy a second GTX 670 for about 200€
2. Sell my GTX 670 for about 200€ and buy a current gen GTX x70 (770 or 870 or whatever it will be in 2014) for 400€

I'll choose option number 2.

I don't know if it is actually disabling CF, but when your game is in fullscreen (which is has to be for CF to work) OBS will only allow use of 1 of my 7970s. The second card drops down to 0% usage.

So my question is, is there a way that you can use OBS while using CF (fullscreen) or am I forced to go pay for an Xsplit sub since I don't want a 400 dollar GPU acting like a brick in my rig while I stream.

Hi, im a noob to the forums so i would like to say hi to everyone and thank you for the software.

To the point of the post.

I also run 2 x XFXHD6870 in crossfire mode, i am also suffering this issue with 1 GPU being disabled when i start the stream. I know this is the case as with ATI cards you can set the option to display the CROSSFIRE logo in the top right of the screen, it disappears when i press start and tab back into game (In this case BLACK OPS 2) i can also tell due to the sudden lack of FPS. A single 6870 running BLACK OPS 2 near max settings (no AA) will run approx 60-80 FPS sometimes 100 2 x 6870s running together i get 140-180fps i can even record at 1080p with PLAYCLAW software at about 120fps as both cards remain active.

After launching OBS and starting then stopping a stream, i also have to restart Black Ops 2 for the CROSSFIRE to be reactivated.

I wish it worked with crossfire, im saddened that it does not, i could stream much better and smoother if i could just use the second card, when attempting to stream 360p i get drops to 45-50 fps average 60, when you are used to 160+ that makes a massive difference to how well you can play, i can get regular scores of 40-5 or similar when not streaming but as soon as i loose my strong FPS i get terrible game plays unless i get lucky.

Do you see any chance of a future update will to allow the continued use of dual gpus? or are you still unaware as to why it does not work?

Thanks for any replies in advance, i love your software and it works better than most, if it worked in crossfire i would definitely contribute to the continued development of this program

Thanks again

Jonas


Full spec:-

2x XFX HD6870 second edition
i5 2500K @4.4Ghz on air cooled with Zalman CNPS9900LED
8GB DDR3 1600 Gskill RipJaw CL9
Asus P8Z68 V-PRO motherboard
Primary HDD is Samsung 840 series 256GB SSD (where OS and BLACK OPS is installed)
Secondary HDD Samsung spinpoint SATA 3.0 1TB 7200rpm
Logitech G510s
Logitech G9x
Turtle Beach PX21

I am not sure about the CrossFire options as I could only afford one AMD but isn't there some option that lets you force the CrossFire into a specific output? What I'm thinking here is that for some reason or another the game, the OS and OBS are not in agreement on which GPU actually is the one showing the output. Or something along those lines.

Just bear with that train of thought for a second.

Again, I cannot check for any possible tweaks to CrossFire that the Catalyst Control Center might allow for as I only have one GPU.