8 Monitors off 2 cards possible?

Sorry if this is answered elsewhere, just running low on time picking up things today for a new system before the cyber Monday deals end and a quick general Google search didn't turn up much.

Wondering if someone could tell me if the following is possible -

I will be running a 6 monitor setup soon but I also need output to a Wacom Cintiq and a TV so 8 displays total. The 6 monitors off 1 AMD card is no problem with either a hub or daisychaining but I'm wondering about the 2 extra as I've never had 2 cards before.

I want Physx, Nvidia 3D on one of my six monitors and six monitor surround/eyefinity support.

I know the new NV cards are 4 output per card vs 6 on AMD with mini DP and hubs/daisy chaining. So ideally I'd buy 2 NV cards for 8 outputs but its stunning to learn the 2nd card's outputs can't be used and I'd need 3 NV cards and due to money, space, noise and heat that's not an option. Plus Even if I did I hear Nvidia Surround can't do 6 monitors no matter how many cards, so I'll still need an AMD for eyefinity.

So this is my plan, just wondering if the following is feasible (and I don't need any card recommendations, I'm up on that):

1. 1 AMD card to run 6 monitors with eyefinity and 1 NV card to run the Cintiq & TV.

Can this be done (running all 8 simultaneously)?

If not, can it be done with 2 AMD cards? With/without crossfire?

2. Can you still run Physx reliably in any way with an NV card dedicated and an AMD as primary?

I know there was a reliable "hack" to do this awhile ago but Nvidia has since disabled it if AMD cards are detected, but doee anyone know if any new semi-reliable at least workarounds have been created? I don't care if the drivers are ancient even as long as it works, I'm looking to do this for older games like Arkham City and Mirror's Edge.

In fact even if there is a way to disable my AMD card (without going into the case and unplugging) this might be OK since running the Physx titles on a single monitor would be okay.

3. One of the 6 eyefinity monitors will be 3D so planning to hook it up to both cards via Kvm switch, so when I flip the switch over to NV could I play games on that monitor in 3D (and/or movies?) despite the AMD drivers and card in system or does Nvidia gimp it if AMD is detected too like with Physx?

Much appreciation for any insight anyone could give and again apologies if these have been answered before, in such a rush today not a lot of time for research. Will check back in later today.

Need more details:

- resolutions of monitors
- CPU/motherboard
- how many monitors to be used in gaming vs SLS when in Eyefinity
- why do you want 6 monitors in Eyefinity? Bezel is in the middle when using 6 monitors, better to go 5.
- do you really *NEED* Physx?

I am running 7 monitors, 4 on AMD and 3 using the onboard Intel 4600 graphics. Depending on the motherboard, video card, and monitor choices it should be possible to achieve at least some of your goals but your description is way too vague to give meaningful feedback.

AFAIK Nvidia physix drivers won't load if there is another card also installed - although there may be a hack / workaround for this nowadays. I stopped looking into this when I started putting AMD cards into some machines.

dvsman said:

AFAIK Nvidia physix drivers won't load if there is another card also installed - although there may be a hack / workaround for this nowadays. I stopped looking into this when I started putting AMD cards into some machines.

Click to expand...

Well I figure it's a longshot but worth some delving.

I'm mostly concerned with being able to still run Nvidia 3D I guess as I'll need to shell out for an Nvidia monitor and if it doesn't work I'm screwed as AMD and Nvidia seem to use different monitor tech (and I'm less a fan of AMD's solution but most importantly I can't find any 24" AMD 3D monitors/with reasonably thin bezels that won't screw up my grouping dimensions).

Not willing to go all Nvidia either as I'm not willing to put 3 cards in my system, noise is a big factor for me plus I don't want to deal with SLI driver hassles (or Crossfire) plus I'd lose more than 5 monitor surround, as an additional minor drawback.

rtangwai said:

Need more details:

- resolutions of monitors
- CPU/motherboard
- how many monitors to be used in gaming vs SLS when in Eyefinity
- why do you want 6 monitors in Eyefinity? Bezel is in the middle when using 6 monitors, better to go 5.
- do you really *NEED* Physx?

I am running 7 monitors, 4 on AMD and 3 using the onboard Intel 4600 graphics. Depending on the motherboard, video card, and monitor choices it should be possible to achieve at least some of your goals but your description is way too vague to give meaningful feedback.

Click to expand...

Appreciate the reply and from the sounds of what you're doing it seems like I'll be able to at least get picture on 8 screens, the most important factor, as you seem to be able to run monitors from 2 separate output manufacturers.

As to the rest of the post, after re-reading I still can't grasp why any more information would be necessary or CPU/mobo. info. Is relevant.

I'm not looking for horsepower advice just technical feasibility to output on 8 screens, CPU/mobo. shouldn't matter so long as it can run (has slots for) 2 VG cards, ditto the resolution.

Maybe I should clarify that while I would like to take advantage of the system Also for games/media, the most important and primary purpose is work, so just getting output on 8 displays (and mostly 7 since the TV will usually be off) is the most important goal.

So most importantly, can I output simultaneously 6 outputs from an AMD card and 3 from an Nvidia card without issues, like, you can have both catalyst and GeForce drivers installed on one system and have things working? I've never had 2 cards before so I have no idea.
As I say I realize doing this on 2 AMD cards might be the way to go but if possible to do it with a secondary as Nvidia as then I can gain some features at least (maybe) such as Nvidia 3d and Physx vs just increased performance via crossfire with 2 AMD cards which is not a big concern for me (+ I'm partial to nvidia's 3d solution and 3d monitors).

But anyway, FYI:

- 7 monitors (6+TV) are 1080p and the Cintiq is 720p
(I guess I can see the importance of not going above 1080p/1920x1200 res. for daisy chaining/Dp hubbing off the AMD card but as I mentioned I have that all worked out, just unsure of going beyond 6 outputs via adding an Nvidia card)

- system not yet built but will be Haswell-e. Asus x99 deluxe, 5820k 6 core, 16 GB of ram

- AMD card will be high-mid or high r9 3XX when it comes out (for gaming). Nvidia card I am thinking something like a gtx 760, don't need power, it just is needed for extra outputs, 3D movies, physx processing if possible and older games in 3D like L4D2, single monitor. Not set in stone though.

Current AMD card is a 6870, good enough for me for now but yes I know it will not be up to game in 6 monitor Eyefinity, just needs to output to 6 screens for now which it can do

- SLS?
Edit: Oh, single large surface? Didn't mention that so I didn't see anyone having that expectation. Anyway, definitely not doing that, just seperate extended desktop windows for everything (and maybe mirrored at times on the TV & Cintiq, but preferably extended).
2nd Edit: Well for gaming I'd try all 6 SLS if I could, heavily degraded but it's fine even if I could only run Portal. Purpose of 6 monitors is work, Eyefinity SLS 6 is a secondary consideration.

- Eyefinity will be 3 for shooters and 6 for some adventure stuff where the bezels don't bother me (got all thin Bezel monitors, 4 are dell u2414h)

In any case that's just for the option, mostly I'll play single screen as I do now with my 3x1 eyefinity setup, not interested in acquiring the horsepower to run everything eyefinity, even when I get an r9 3XX card (too much noise and expense for me)

- my monitor arm solution is stacked as 3 by 2, for work/productivity purposes, hence the configuration (and hey maybe I can get another row up top for 3 by 3 gaming one day when money is no object and the Bezel issue will be solved... Of, course, by then it'll probably make more sense to use a giant res. curved big screen TV, 8K or something)

- Well no one *needs* Physx but it objectively makes the game look better and more immersive, if purely cosmetic. So I don't need it no but if I can get it I will. I want it more than I want crossfire. Plus a beefy AMD card and efficient Nvidia one makes more sense for me than 2 mid or high end AMD cards since I like to run silenced systems.

Anyway, wasn't asking for a tutorial just if someone knows I figured it'd be here and someone could point me somewhere to go on it.

Still though would like info. on running Nvidia 3D and the 8 display thing with an AMD and NV card if anyone can confirm/provide more info., would be much appreciated.

And thanks again for the info. thus far.

If the TV and Wacom device don't need 3D accelerated output, a USB graphics adapter would be enough.

AFAIK NVidia does no longer allow GPU PhysX in systems where an AMD card is present.

chithanh said:

If the TV and Wacom device don't need 3D accelerated output, a USB graphics adapter would be enough.

AFAIK NVidia does no longer allow GPU PhysX in systems where an AMD card is present.

Click to expand...

Not sure what that entails (needing "3D accelerated output", ie. having vs not having), but definitely not planning to go the USB route, read too many stories of flaky limited hardware + none of the possible benefits of an NV secondary card + not that much of a savings for the type of card I plan to get.

(If I understood that right.)

Also just remembered another possible benefit of getting an Nvidia card as my secondary card is so I could use an Nvidia Shield device if I ever have money to throw at one (and hopefully not also disabled by detecting an AMD card in the same system).

On the Physx thing, well I heard the "easy/works for everything widespread-method" was over but also figured and heard somewhere people are still trying to work out solutions which now seems to be confirmed as so by this not too old thread I found -

http://hardforum.com/showthread.php?t=1792373

Information on the new r9 3xx is still uncertain. But i dont think you will be able to achieve playable frame rate with 1 r9 290x, Maybe sli set up would help solve the issue.

gungravevn said:

Information on the new r9 3xx is still uncertain. But i dont think you will be able to achieve playable frame rate with 1 r9 290x, Maybe sli set up would help solve the issue.

Click to expand...

[Can skip the last bit under the long line of stars if not interested.]

Whether it's called r9 3XX or something else doesn't matter, I can wait for AMD's new process card series.

I can output to 6 monitors now even off of my meager 6870.

As far as gaming power is concerned, again, for the purposes of this thread that stuff doesn't matter. I can figure out what's optimal later on my own and acquire that, the main thing is I need to hook up 8 displays and need to know if it's technically feasible with an AMD card and an Nvidia card for monitors 7 & 8.

The main/most important purpose of the main 6 grouping of monitors is work, not Eyefinity, but that said if I'm going to have six monitors I'd like the option at least to take advantage of Eyefinity/Surround for 6 monitors.

And that's not in doubt, well documented that Eyefinity 6 is (technically) possible on single cards.

Most of the time I'll probably be gaming in 3x1 or even on a single monitor as I do usually still with my current 3x1 setup. The six monitors are for work but since they're there I'd just like the option on occaision to take advantage of all six if feel like it for gaming.

I've ruled out SLI (which I would have preferred to use) for several reasons.

1. Nvidia cards do 4 monitors. A 2nd nvidia card, unbelievably, can not be taken advantage of to add more displays, just it's horsepower for SLI. So that means 3 Nvidia cards for 8 displays.

But to me that's pretty much no dice based on both expense and because I run a silent system (more expense and headache to silence 3 cards, if even possible).

Plus I'm not big on SLI/Crossfire if I can avoid those hassles.

(Not such a big deal nowadays I know but for me still not too interested. Plus a silent system is paramount to me and that's sorta anti-thetical to that. Only going to be running 2 cards now because I must, if I could output to 8 displays off a single [mainstream] card now I would.)

I'll re-examine this route if I have to, but I think there is a better solution.

2. Even if I got 3 Nvidia cards running in Sli, Nvidia Surround is capped at 5 screens.
And I can't put 5 screens vertical (and wouldn't want to even if I could, especially since the system is not just for gaming) because my monitor arm setup only allows 2 rows of 3 and using that is a must, just bought it (SpaceCo. SpaceArm).

Which means even if I went with 3 card Sli and somehow cooled it I'm basically stuck at the same 3 screen surround setup I can do now on my 6870.

Considering the expense of all these monitors, a new system and new video cards (especially 3), that seems to me kinda a waste if I can't even take advantage of all my screens, plus not even increasing my capability beyond my current 3 screen setup is not an acceptable solution given all the expense (and hassle of 3 card Sli), even if it means I would get all the Nvidia proprietary goodness I want.

So that basically has me concluding at least 1 (primary) card must be AMD if I want to stick to 2 cards or go beyond 3 screen surround gaming (specifically 6).

***

Need 8 displays (for work purposes, only up to 6 for gaming) and Nvidia 3D due to 3D monitor choice/needs.

Just need to know IF it is possible to do that with 1 AMD card and 1 Nvidia card in the same system (PCIe).

***

Want Physx, 6 monitor surround gaming, only 2 video cards, no Sli/Crossfire hassle, and even Shield streaming, if I could get them all.

I realize these are in 2 separate ecosystems so I am trying to have my cake and eat it too... but hey, if I can do it then dammit why not? Even if it's a hassle to me it's worth it.

Physx/shield stuff is not a dealbraker, but I'd like to try if I can.

A 2 card solution might be easier on 2 AMD cards plus I'd get crossfire (don't want but if I had 2 AMD cards of course I'd do) but then I'd lose Nvidia 3D which I'd REALLY prefer and any chance at other cool Nvidia tech (Physx/Shield) via hacks for only more horsepower (crossfire) which is not as appealing to me.

But I really don't even know still if this can be done (8 displays) off even 2 AMD cards, let alone an AMD and Nvidia card (8 displays). So if someone could answer definitively for either I'd appreciate it.


****************************************************************

[This section is just me explaining my rationale for those interested, I know this is getting long, so otherwise consider here the end of my post].

So if I have to go 2 AMDs I will but if I can output to 8 displays on 1 AMD card & 1 Nvidia card I'll do it because:

- chance at physx/shield capabilities

- only need 2 more displays beyond 6 (8), so only gaining another possible 4 displays via Nvidia vs another 6 (12 total) with a 2nd AMD (maybe?) doesn't matter

- Nvidia card will be hooked up to TV and Cintiq so it's okay if it's not beastly, primary gaming done on the 6 monitor grouping (and if I wanted to do couch gaming I think I could hook up some KVMs off the AMD to switch off 1 of the 6 and switch on the TV as number 6/primary I think)

- I would prefer Nvidia 3D because, aside from the solution I think being better (though not a dealbreaker), if proprietary (unfortunate), AMD 3D monitors suck for my purposes.

All my monitors are thin bezel:

--- 4 are 24" Dell U2414H, very slim, maybe the slimmest

--- bottom middle is a Viewsonic TD2420 (need a touch for work purposes, testing touch control software, 2 point touch only unfortunately but the only relatively slim Bezel 24" touch monitor compatible with Windows 8 (yes, they sell Win. 7 only touch monitors, looking at Planar... even if acceptable now, not when Windows 10 comes out) I could find, in a slim field, other than the discontinued Samsung SC770 which in typical Samsung fashion didn't have Vesa mounts anyway but was otherwise perfect and 10 point touch)

--- Top middle will be the 3D monitor (part of 6 monitor Eyefinity gaming group but also hooked up to Kvm for Nvidia card for single screen 3d gaming/movie watching)
Just ordered the Benq XL2420Z on sale from black Friday (no NV card yet though so I hope I don't have to return it), which has relatively slim bezels and should be in good proportion roughly with the Viewsonic touch below it and not screw up the Eyefinity setup alignment

AMD 3D sucks for me because of the hardware, not the software. When I checked (at least a few months ago) I either didn't see anything 24" 3D or if I did the bezels were not acceptably small enough to be part of my 6 monitor Eyefinity grouping.

+ I don't see any tech like Lightboost on AMD's side so it seems clear to me as not being the optimal ecosystem to invest in for 3D.

- Single Nvidia card (thinking gtx 760) doesn't need to be beefy since it would only be used for outputs, physx processing and single screen 1080p 3D gaming, so easy to keep cool and quiet, which is also very important to me

- Lastly, an AMD/NV solution I think will be -just fine- on power vs crossfire solution because:

--- For Physx stuff, there should be no framerate hit if I get the nvida card doing it, except on 3.0 where I hear that the hack doesn't work, so it will be disabled anyway
--- Will have a kickass CPU (6 core 5820k i7 Haswell e)
--- maybe in the future an improved ddr4 upgrade will offer more benefit? Got 16 GB for now at least anyway

--- Most importantly, I'm not worried about using a single AMD GPU at all for gaming. Why? Well:

----- Even with my silence concerns on top of the single card limitation I don't feel limited. Prolimatech MK-26 heatsink is the best out there as I understand it and can cool ANYTHING dead silent with a couple 120mm Nexus fans, barring heavy OC'ing (check out the Silentpcreview and amazon reviews), so that doesn't worry me and lets me get even a flagahip card

----- I do expect a good increase from r9 3XX, but even if only as good as gtx 900 series, which I doubt, that's enough for me

----- No problems waiting for it. My meager 6870 can output (for work purposes) to 6 screens while I wait and game good enough for single monitor and occasional 3x1 stuff for my
purposes. My Steam backlog is LONG. Not playing Watch Dogs/new Metro type stuff, more Hitman/Arkham City level stuff

----- Most of my gaming will probably be 3x1 or even single screen, which is fine

----- Again, I got the 6 monitors not for gaming but for work, but, since I have them, sure I'll take advantage of all 6 for occasional gaming if I can. Obviously a beefy crossfire/sli setup would be optimal if this is the way I plan to play most things. I don't. Obviously all AA, AF and crazy effects will be off, maybe even a resolution downgrade. It'd be cool if I could play something like Arkham City as such 6 screen on a high end or the flagship r9 3XX card, that's my expectations.

But, even if I couldn't, I wouldn't care. If I could only play stuff like Portal in 6 screen I'd be happy. Hell I can play it fine 3x1 now with most stuff on with my 6870, so I'm pretty sure an r9 3XX card will handle it no problem. I'll even try Portal 6 screen (heavily degraded) on my 6870 when I get my system together, not sure what to expect.

But again for now as long as I get my 8 screens outputted to for work purposes that is what I care about.

***

Other Q's:

Why not buy an r9 290X?

- If I'm going to put down big money on AMD single gfx card I want it to last 2 or 3 years, I can't see that as much with the 290x, etc. cards.
- Be nice to have a card support Displayport 1.3 for the future and fully support (or more fully) DX 12, regardless of what they claim on that now for current cards
- No burning need to upgrade. 6870 ok for what I do now single screen most anything out

Why more than 6 monitors anyway?

- AMD does 6, wanted more than 3, saw a good 6 monitor mount, forgot I have (and need) the Cintiq there too. TV is in the room so why not, plus I can use it for couch gaming, 2nd card is cheaper than an HTPC.

Can't you KVM the extras & turn off a couple monitors to use the TV and Cintiq?

- I guess but I'd like all 8 and the possible Nvidia ecosystem benefits if I can
- Might want to use all 6 monitors while someone else in room uses TV to watch a movie from the PC
- As said above, AMD 3D monitor dimensions available screws up my eyefinity hardware grouping's dimensions so I kinda need to get an Nvidia card anyway if I want to get 3D, which I do. No room to keep an extra monitor to the side for AMD 3D plus I don't want the expense of an extra monitor

Need that many monitors for work, what for?

- Maybe not but I know so far I'd like more than 3 and on Vesa mounts. Work stuff is multimedia work and game dev. (indie/mobile level, hence the touchscreen monitor for testing purposes). TV hookup and 3D monitor is purely for entertainment purposes I must admit though. Cintiq for art obviously.

Wouldn't it be better for you if you had X number of cards and X better CPU, etc. components?

- If I had the money. New system and ergonomic workstation setup is already costing a small fortune.

***

Sorry for the wall of text but if you got through all of that hopefully it clarifies any question that could be had.

And sorry for any poor spelling/weird jarring capitalizations, reno.-ing my room so no PC access, typed this on tablet.

JMSNorthern said:

As to the rest of the post, after re-reading I still can't grasp why any more information would be necessary or CPU/mobo. info. Is relevant.

Click to expand...

The reason I asked for the CPU/mobo is that if it is Intel you may have 2 or 3 display outputs from the onboard graphics. That means if you got a single video card with 5 or 6 output eg. R9 295x2 you're set because the other 2 or 3 monitors could be driven by the Intel graphics.

If you have an AMD FX series CPU then you'll need either a specialist card like Matrox or 2 video cards.

I may be missing something here, (Never dealt with SLI/Crossfire, and generally have used ATI cards) but if there are nVidia cards that support 4 monitors simultaneously, (My ATI card HD5770 has 4 ports, but I think it can only drive 3 monitors, (I only ever use 1)) I think you should be able to install 2 nVidia cards without the SLI bridge, and have all 8 outputs work. what kind of performance you'd get out of your games is another matter entirely, and may have to do with how you connect the monitors to the cards.

rtangwai said:

The reason I asked for the CPU/mobo is that if it is Intel you may have 2 or 3 display outputs from the onboard graphics. That means if you got a single video card with 5 or 6 output eg. R9 295x2 you're set because the other 2 or 3 monitors could be driven by the Intel graphics.

If you have an AMD FX series CPU then you'll need either a specialist card like Matrox or 2 video cards.

Click to expand...

Yeah, well, unfortunately that solution is not ideal for me since I'm buying (well, have bought) an Nvidia 3D monitor (AMD ones I've seen are out of the question due to bezel thickness) and I don't think there is any way around the card requirement there.

Hope Ultra D or someone else hurries up with the glasses-free 3D displays being released and this glasses ecosystem crap can end, probably next year.

Also while that Intel solution sounds awesome on the cheap, I'm really more concerned about feature capabilitiy than cost (though not infinitely so).

But yeah I'm ASUS x99 Deluxe and Haswell e so no Intel gfx for me.

Anyway, not got anything confirmed yet still but feeling more certain I can pull it all (or most) off the way I wanted now. System ordered but 3D vision kits were out of stock so I'll have to try and pick that and the Nvidia card up on boxing day.

tdowning said:

I may be missing something here, (Never dealt with SLI/Crossfire, and generally have used ATI cards) but if there are nVidia cards that support 4 monitors simultaneously, (My ATI card HD5770 has 4 ports, but I think it can only drive 3 monitors, (I only ever use 1)) I think you should be able to install 2 nVidia cards without the SLI bridge, and have all 8 outputs work. what kind of performance you'd get out of your games is another matter entirely, and may have to do with how you connect the monitors to the cards.

Click to expand...

That was my initial logic as well but I thought I read somewhere that the second card's outputs would be rendered disabled and you'd need 3. Though on looking again that may have been referring to SLI mode only. Doing a bunch of different searches on this now is turning up all sorts of conflicting information for Nvidia cards over 4 displays.

If I did have to go that way though it would be a shame to have my 6 monitor setup and never be able to use them all for gaming since Nvidia doesn't support that many no matter how many cards.

In any case I have an AMD card already that supports 2 monitors (DVI/DVI or DVI/HDMI) and has 2 mini-dp ports (already tested as outputting to 4 displays successfully) that will let me take things to 6 outputs via a DP hub or via daisy chaining my Dell U2414H's, as I understand it.

So if I buy an Nvidia card to cover the extra displays and it all works together, great, and if I have to go with 2 nVidia cards as you suggest, well, at least I'll have one already I can double up.

(Thinking a Gtx 760, not a ton of power but price is right and still more powerful than my current stopgap 6870.)

Of course if neither of those solutions work and I really just need 2 AMD cards or 3 Nvidia cards then I may really be screwed but hopefully that won't happen or I can return some things.

I'll definitely post my results anyway for anyone curious when done (probably next month) but still hoping there's maybe someone out there in the know who can confirm or disconfirm any of this before I pull the trigger on an Nvidia card on boxing day.

***

So another question to anyone out there who knows:

Will running 8 monitors off 2 (same) 4 output Nvidia cards work or is 3 needed?

If it does work on 2, is that only in non-SLI mode?

(I know I can't get Nvidia Surround gaming to 6 or more of course though.)

Not trying to be lazy but I have tried researching this a bunch and have found trouble turning up much at all let alone anything definitive.

Dtrox1 said:

Wow, this is a lot to take in. Most cards support only 3 displays, even if they have 4 out ports. I know the 900 series Nvidia cards support 4 per card. I can't say much on the ATI side.

Click to expand...

Yeah it's a bit of a specialized case I acknowledge but I figured before I threw down money if anyone would know it might be someone here.

I think you're right most cards are 3 display now (lower end AMD) or 2 display for lower end Nvidia (just a hunch, haven't checked).

Modern mid-high and high end Nvidia seems to be 4 display and my understanding is most mid-high and high end 6800 series and up Amd cards can be pushed to 6 displays:

2 from DVI/DVI or HDMI/DVI and there's often another 2 mini-displayports available which gets you to 4 with active DP Adaptors (already doing this with my 6870) but with Dp 1.2 my understanding is you can attach a 3 port $100 hub to either mini-displayport and use it to output to up to 3 monitors (at 1080/1200p 60fps) per mini-dp port via the hub, though no more than 6 total from the card overall, without needing to buy those Eyefinity 6 (6 mini-dp outputs on it) cards anymore.

Or you can output to up to 4 displays off 1 mini-dp port at 1080p 60fps (maybe 1200p too) if you connect it to a DP 1.2 monitor that supports daisy chaining like my just ordered 4 Dell U2414H monitors fortunately, just linking one monitor up to the next.

4 Cards off of each video card is usually very easy if the device either has the appropriate ports or you use a MST DisplayPort hub (purchased separately) (and the video card has a DisplayPort).

However, since Vista and the architectural changes made under the hood with WDM, DWM and the GPU Acceleration APIs, running any GPU accelerated applications on any monitor powered by the non-primary video card results in sub-par performance (churning of GPU and GPU Ram). The churning happens because Microsoft engineers decided it's smart to pin all GPU Work on the primary video card.

Any GPU Accelerated App on the second video card transfers to primary video card does the work and returns the result to the secondary video card. This results in high GPU Usage and GPU Ram use spikes.

At a certain point DWM kills itself based upon an excessive resource urage algorithm that is based upon the amount of video ram you have versus the amount that is currently allocated (spiked). The amount of physical ram you may have might also come into play.

Most people don't seem to notice it as it's related to the number of applications that use GPU Accelerated API (browsers/video card etc) that are running on the second monitor. However the side effects are DWM being constantly reset/Aero disabled/warnings about Windows performing slowly/prompts to disable aero.


The Summary/TLDR version is that this unfortunately Running monitors off of a secondary video card can sometimes be a bit painful depending upon your usage of the monitors. Any application that uses the Windows GPU Accecleration API (Your browsers, most video players, etc) will run afoul of this if they are displaying on a monitor being powered by the non-primary video card.

JMSNorthern said:

2 from DVI/DVI or HDMI/DVI and there's often another 2 mini-displayports available which gets you to 4 with active DP Adaptors (already doing this with my 6870) but with Dp 1.2 my understanding is you can attach a 3 port $100 hub to either mini-displayport and use it to output to up to 3 monitors (at 1080/1200p 60fps) per mini-dp port via the hub, though no more than 6 total from the card overall, without needing to buy those Eyefinity 6 (6 mini-dp outputs on it) cards anymore.

Click to expand...

Correct: I'm using StarTech.com MSTMDP123DP Mini DisplayPort 1.2 to Triple Head DisplayPort Multi Monitor MST Hub

3 DP and 1 DVI. I have to R7 2xx series but I got tired of DWM killing itself

The adapter is okay - however it should be noted that it requires a single mDP. My Video Card didn't have it and it took two takes before i found the right connector.

I do get a bit of random 2-3 blackouts on one or all DP monitors and I am unsure what that's related to (maybe once or twice a day).

Thanks Major your post was very enlightening. Now regarding:

Fort_Major said:

The Summary/TLDR version is that this unfortunately Running monitors off of a secondary video card can sometimes be a bit painful depending upon your usage of the monitors. Any application that uses the Windows GPU Accecleration API (Your browsers, most video players, etc) will run afoul of this if they are displaying on a monitor being powered by the non-primary video card.

Click to expand...

Do you know if/think this resource issue would still likely be an issue supposing I switched 1 of my 6 monitors hooked to my AMD card, off of the AMD card and over to a secondary Nvidia card for 3D gaming/3D movie watching?

I gather the implication is yes, but assuming I could get an AMD and nvidia to work together fine in the system in the first place, my thinking is since the Nvidia 3D vision games/kit requires Nvidia hardware to work, windows would have no choice but to have stuff (the 3D movie or Nvidia game) for the 3d monitor hooked to the Nvidia hardware and bypass the AMD primary card, at least for that.

Plus even if the AMD card was somehow still involved, it would be down to using 5 of 6 displays so perhaps that would make room to help the secondary card?

And if none of that works, presumably I could just enable the Nvidia card as primary temporarily while 3d gaming/movie watching and if any issues are caused on the AMD displays, well I guess it wouldn't matter since my attention wouldn't be on them at that time as it'd only be temporary?

This whole thing seems to present so many questions I'll be eager to start getting answers once I get all the hardware together, will be sure to report results here.

Fort_Major said:

Correct: I'm using StarTech.com MSTMDP123DP Mini DisplayPort 1.2 to Triple Head DisplayPort Multi Monitor MST Hub

3 DP and 1 DVI. I have to R7 2xx series but I got tired of DWM killing itself

The adapter is okay - however it should be noted that it requires a single mDP. My Video Card didn't have it and it took two takes before i found the right connector.

I do get a bit of random 2-3 blackouts on one or all DP monitors and I am unsure what that's related to (maybe once or twice a day).

Click to expand...

Hmm, does your card not have 2 mini-DPs and either 2 DVIs or a DVI and HDMI port? I kmow not all higher end vendor cards do unfortunately.

I currently run 4 monitors off a 6870, all 1080p/60 fps without issue. I use the HDMI, a DVI and the two mini-DPs with active adaptors then converted to DVI, no hub. Setup is generally 3 productivity, 1 (TV) video, all separate displays, or 3 eyefinity gaming and TV for video (though it's rare I've had the TV on while eyefinity gaming).

Never had any flickering, stuttering or blackout issues for that, so I wonder if it's maybe the hub causing your issues? I wonder, if you tried something like my setup if your issues would be resolved? (Though I imagine if you had 2 mini-DPs you wouldn't have bought the hub. I know a few modern AMD cards don't have 2 mini-DPs but I always find it strange to see, lazy vendors.)

I unfortunately don't have the multiple display ports. Not sure how I missed that when choosing the card beacuse I thought I explicitly checked for multiple display ports. Cards have 2 DVI, 1 HDMI, 1 DisplayPort (regular size) each.

I'm pretty sure it's the hub that's doing it. But the random flickering is far better than all of the issues I was having running 2x DVI off of both Video Cards with DWM with Microsoft's stupid pinning all GPU Accelerated applications to your primary video card.

I would honestly stay away from mixing Nvidia and AMD. I know that Microsoft claims to have (re) fixed mixing of video cards but since they broke multiple video cards for all systems and appear to have no plans on fixing the pinning issue, (because most "consumers" who have multiple video cards use SLI and the issue doesn't show up with SLI)

JMSNorthern said:

Thanks Major your post was very enlightening. Now regarding:



Do you know if/think this resource issue would still likely be an issue supposing I switched 1 of my 6 monitors hooked to my AMD card, off of the AMD card and over to a secondary Nvidia card for 3D gaming/3D movie watching?

Click to expand...

This problem happens on any system that has multiple video cards in a non-SLI output where you're viewing any application that uses Microsoft's GPU Acceleration API that is on a monitor that is the non-primary video card.

And unfortunately all browsers use GPU Acceleration.

The bug is verified in Windows 7 and Windows 8. I assume it's in Windows Vista because that's where the changes took place, but who uses Vista.

I will also assume that the problem will permanently exist in Windows and so most likely exists in 10 since Microsoft is constantly catering to the "80% of their consumers and power users make up <2-5% of their market share" and according to Microsoft it was an unsolvable engineering problem. (Though why they don't just pin apps to the video card that they're being displayed on....)