Dual Display - 2nd Display using iGPU

[ElmoTheMuppet]

I was wondering if anyone has a setup that has their primary display using their dedicated gpu and their second display using their iGPU (integrated graphics on the cpu) and have games only running on the primary display. How is the performance compared to having both displays running on the dedicated gpu?

 

Does your dedicated gpu have lower temps while idle or gaming, with this setup?

Do games running on the primary display have higher minimum frame rate, with this setup?

Any known issues with this setup?

Does it depend on the type of iGPU being used?

 

[obobski]

I've not done this with a CPU-built-in-GPU (haven't had a need to...yet), but I've done this kind of configuration in the past with multiple graphics cards, IGPs, etc and here's roughly my experience/opinion on the matter:

 

- Historically speaking the dedicated GPU will run coolest by itself driving one or two monitors, unless the second GPU doesn't impact airflow (e.g. is built-in to the chipset), however that second GPU will produce heat of its own. Modern GPUs don't align with this as closely though - their dynamic clocking will change behavior in single or multi-monitor configurations, and they tend to run a little warmer when driving multiple displays (it should be nothing to worry about but it's just something to keep in mind).

 

- Adding a second GPU that isn't from the same maker as the primary GPU will not work in Windows Vista, but it will work in XP and 7 (I do not know if it will or won't work in 8/10). It will require drivers for both. This can increase memory usage and create some conflicts having two different graphics drivers installed; it's nothing that can't be managed (well, okay, 3DLabs drivers really DESPISE sharing a machine with anything else, but you're unlikely to have a 3DLabs card), but it can be annoying sometimes. Much better to go all from the same maker (e.g. nVidia + nVidia).

 

- A lot of games will not handle losing focus for some application/stuff for whatever is on the second monitor, no matter what GPU is driving what display or handling the game. Bethesda games are probably among the worst for this. This has to do with how DirectX handles application focus and loss of focus, and some games simply do not recover from it very well. There are other games that do very well with this (e.g. Empire Total War will let you minimize it), however you will still have to deal with the limitations of DirectX (the renderer has to re-initialize when focus is regained; ETW will show a loading screen while this happens, some games will just show a blank screen, etc). Running the game in a window may help this for some games, so that may be worth looking into.

 

- Depending on what you're doing on monitor #2 may also heavily impact performance, for example if you want to watch a Blu-ray, play a videogame, browse the web, and have video chat open all at once, you're going to likely have performance issues with at least some of those applications (e.g. sometimes you may have stutter in the game or frames dropped in the video as the machine load balances all of that). Having multiple GPUs can help if you're doing stuff that's GPU accelerated, but it's not foolproof.

 

- If you just want to drop secondary outputs from the primary GPU onto another card in the hopes of gaining performance, I wouldn't bother - it usually makes no nevermind if the secondary outputs aren't being used (even if they're just drawing the desktop but not disabled), at least based on my experience.

 

Some other stuff to consider:

 

- If you have nVidia, you can add another nVidia card and use it for secondary monitors and also throw PhysX onto it. This may or may not help performance depending on specific hardware and what you're doing. It's "free" though, if you have two nVidia cards.

 

- The iGPU being enabled in your CPU may increase CPU temperatures and it will also share memory bandwidth with the system, this could lead to a performance hit depending on what-all you're asking the machine to do at once.

 

- Having an Intel iGPU enabled may cause conflicts with some games that try to specifically block Intel GPUs. I don't actually know too much about this overall, I've just read of some games over the years explicitly trying to block any Intel GPU, and imagine it could be a potential problem even if you're trying to get the game to run on your nVidia/AMD card.

 

- nVidia will block PhysX if third-party GPUs are supported, broadly speaking.

 

- Having multiple separate graphics drivers installed can make configuring some games interesting, as the game may want to default to an adapter/monitor/etc that isn't where you'd like it, or it may not properly identify all of your available output options. Some games also really just do not like multi-monitor configurations.

 

Overall I would say there isn't a definitive "yes do this" or "no don't do this" that I could give you. It can be an entirely workable solution, but it isn't the only way to achieve what you're wanting, especially in the era of graphics cards commonly having 3-6 output channels. I would suggest looking at what you already have, hardware wise, and seeing what kinds of other options are available (e.g. buying another PCIe card, upgrading your current graphics card, etc) and going from there. It's also worth considering what games you're primarily wanting to do this with - some are more friendly to it than others.

 

Finally, a completely off-the-wall idea:

 

While I've experienced problems with many games trying to run on a multi-monitor system and multi-task while gaming, I've not had problems with any game I've tested and InputDirector hooked up with a second machine. In that configuration you'd have PC A running your game into Monitor A, and PC B running whatever you want into Monitor B, and you just run the mouse pointer off-screen (you can lock it on-off screen with hotkeys to prevent "losing control" in the middle of gaming) and do whatever you need on the secondary machine. Even Skyrim seems to have no problem with this, and I've happily watched many a DVD while dungeon crawling. The downsides here are that InputDirector only supports Windows 2000 through Windows 7 (I've heard a lot of mixed things about Windows 8), and will require multiple PCs. Just food for thought.

[MotoSxorpio]

Bob seems to know what he's on about...but I'm gonna spew stuff in layman's terms :D no offense, bob. I luv ya, mang.

 

It all depends on your hardware. Those new A10 AMD are pretty nice for Win 8+...seem to blaze along. My dad has an A8 with decent iGPU and miniGPUdiscrete. Its damn fast, compared to my PC here. Very responsive. I've hooked it up to an external tv/monitor before, and played videos etc on it. While that isn't like playing Skyrim, it does show a bit about how well it performs. To save folks like Bob up there some breath, cuz he's thorough, You might explain the reasoning behind asking such a question, perhaps there are alternatives.

 

Now, Getting an answer that actually pertains to your wishes really relies on why you need the information. ;) Good luck, and happy gaming! :dance:

[obobski]

Bob seems to know what he's on about...but I'm gonna spew stuff in layman's terms :D no offense, bob. I luv ya, mang.

 

It all depends on your hardware. Those new A10 AMD are pretty nice for Win 8+...seem to blaze along. My dad has an A8 with decent iGPU and miniGPUdiscrete. Its damn fast, compared to my PC here. Very responsive. I've hooked it up to an external tv/monitor before, and played videos etc on it. While that isn't like playing Skyrim, it does show a bit about how well it performs. To save folks like Bob up there some breath, cuz he's thorough, You might explain the reasoning behind asking such a question, perhaps there are alternatives.

 

Now, Getting an answer that actually pertains to your wishes really relies on why you need the information. :wink: Good luck, and happy gaming! :dance:

 

Good point on the APU and latency - I wish I could find the AMD presentation from a few years ago (its probably buried somewhere on their developer site), but they demonstrated one of their old-ish APUs (Trinity I think) against Radeon HD 5870, and showed significantly lower latency - the 5870 only had an advantage when the task exceeded the APU's computational abilities (e.g. running Skyrim). For decoding HD video or DVDs and so forth any semi-modern graphics solution (from the lowliest Intel IGP on up) should provide full h/w acceleration, as long as the software behind it is working and configured correctly. That last bit is important to keep in mind, because IME "just works" is still kind of an idealized scenario when dealing with different media players, codec packages, media containers/formats, etc. Trial and error is still necessary, at least to some extent. Something else to consider if you're adding another graphics card for a modern system - ensure that it is new enough to support said decoding features; there are cases where a newer, slower card has a leg-up here over something faster but somewhat older. Generally the cutoffs for discrete cards are GeForce 8600 and above and Radeon HD 4000 series and above; for IGPs the Radeon 3000 series and above (must have UVD2.x; some do and some do not), Intel 4500HD and newer (the "plain" 4500 is not the same), and all of the AMD APUs should be suitable.

[ElmoTheMuppet]

I've not done this with a CPU-built-in-GPU (haven't had a need to...yet), but I've done this kind of configuration in the past with multiple graphics cards, IGPs, etc and here's roughly my experience/opinion on the matter:

 

- Historically speaking the dedicated GPU will run coolest by itself driving one or two monitors, unless the second GPU doesn't impact airflow (e.g. is built-in to the chipset), however that second GPU will produce heat of its own. Modern GPUs don't align with this as closely though - their dynamic clocking will change behavior in single or multi-monitor configurations, and they tend to run a little warmer when driving multiple displays (it should be nothing to worry about but it's just something to keep in mind).

 

- Adding a second GPU that isn't from the same maker as the primary GPU will not work in Windows Vista, but it will work in XP and 7 (I do not know if it will or won't work in 8/10). It will require drivers for both. This can increase memory usage and create some conflicts having two different graphics drivers installed; it's nothing that can't be managed (well, okay, 3DLabs drivers really DESPISE sharing a machine with anything else, but you're unlikely to have a 3DLabs card), but it can be annoying sometimes. Much better to go all from the same maker (e.g. nVidia + nVidia).

 

- A lot of games will not handle losing focus for some application/stuff for whatever is on the second monitor, no matter what GPU is driving what display or handling the game. Bethesda games are probably among the worst for this. This has to do with how DirectX handles application focus and loss of focus, and some games simply do not recover from it very well. There are other games that do very well with this (e.g. Empire Total War will let you minimize it), however you will still have to deal with the limitations of DirectX (the renderer has to re-initialize when focus is regained; ETW will show a loading screen while this happens, some games will just show a blank screen, etc). Running the game in a window may help this for some games, so that may be worth looking into.

 

- Depending on what you're doing on monitor #2 may also heavily impact performance, for example if you want to watch a Blu-ray, play a videogame, browse the web, and have video chat open all at once, you're going to likely have performance issues with at least some of those applications (e.g. sometimes you may have stutter in the game or frames dropped in the video as the machine load balances all of that). Having multiple GPUs can help if you're doing stuff that's GPU accelerated, but it's not foolproof.

 

- If you just want to drop secondary outputs from the primary GPU onto another card in the hopes of gaining performance, I wouldn't bother - it usually makes no nevermind if the secondary outputs aren't being used (even if they're just drawing the desktop but not disabled), at least based on my experience.

 

Some other stuff to consider:

 

- If you have nVidia, you can add another nVidia card and use it for secondary monitors and also throw PhysX onto it. This may or may not help performance depending on specific hardware and what you're doing. It's "free" though, if you have two nVidia cards.

 

- The iGPU being enabled in your CPU may increase CPU temperatures and it will also share memory bandwidth with the system, this could lead to a performance hit depending on what-all you're asking the machine to do at once.

 

- Having an Intel iGPU enabled may cause conflicts with some games that try to specifically block Intel GPUs. I don't actually know too much about this overall, I've just read of some games over the years explicitly trying to block any Intel GPU, and imagine it could be a potential problem even if you're trying to get the game to run on your nVidia/AMD card.

 

- nVidia will block PhysX if third-party GPUs are supported, broadly speaking.

 

- Having multiple separate graphics drivers installed can make configuring some games interesting, as the game may want to default to an adapter/monitor/etc that isn't where you'd like it, or it may not properly identify all of your available output options. Some games also really just do not like multi-monitor configurations.

 

Overall I would say there isn't a definitive "yes do this" or "no don't do this" that I could give you. It can be an entirely workable solution, but it isn't the only way to achieve what you're wanting, especially in the era of graphics cards commonly having 3-6 output channels. I would suggest looking at what you already have, hardware wise, and seeing what kinds of other options are available (e.g. buying another PCIe card, upgrading your current graphics card, etc) and going from there. It's also worth considering what games you're primarily wanting to do this with - some are more friendly to it than others.

 

Finally, a completely off-the-wall idea:

 

While I've experienced problems with many games trying to run on a multi-monitor system and multi-task while gaming, I've not had problems with any game I've tested and InputDirector hooked up with a second machine. In that configuration you'd have PC A running your game into Monitor A, and PC B running whatever you want into Monitor B, and you just run the mouse pointer off-screen (you can lock it on-off screen with hotkeys to prevent "losing control" in the middle of gaming) and do whatever you need on the secondary machine. Even Skyrim seems to have no problem with this, and I've happily watched many a DVD while dungeon crawling. The downsides here are that InputDirector only supports Windows 2000 through Windows 7 (I've heard a lot of mixed things about Windows :cool:, and will require multiple PCs. Just food for thought.

Thank you, obobski. You explained that very well. I wish there were thank you buttons so I don't have to bump topics everywhere.

[obobski]

Something else I thought of, and realized I did not post:

 

If you're going to go with two cards from the same manufacturer, for example nVidia + nVidia, they will need to run a common driver (at least this has consistently been my experience). This generally is not a problem within reason, but it may restrict your ability to get updates if you want to run a relatively old card, and there will be compatibility issues at the "outer edges" (e.g. lets say you want to run a GeForce 6800 and GTX 980 together) as there won't be a common driver. I'm not sure how this would play out with an AMD APU + Radeon graphics card, but it's worth keeping in mind if that's the kind of configuration you want.

Edited August 3, 2015 by obobski