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Currently I have a Quadro FX 580 graphic card, which does job well for visual projects and rendering. However, for this days computer games it would struggle a lot and I'm thinking about getting extra graphic card like GTX 560 Ti and connect them via KVM switch to single monitor.

My motherboard which is P7P55D series support multiple graphic cards but I'm not sure would they work together or not and what kind of conflicts I might dealing with?

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migrated from Mar 22 '11 at 6:56

This question came from our site for system and network administrators.

Run two different video cards from the two manufacturers: one from AMD and one from Nvidia. Then reset the CMOS Source – Randy Appointment Apr 30 '13 at 22:16

They should work just fine. I think the limiting factor (and the reason I think this is a bad plan) is the use of a KVM. Most KVMs I'm aware of seriously hurt video bandwidth (make the image fuzzier / less sharp), which would be kind of a waste w/r/t the fancy video cards.

Sure, SLI would be nice, but if the two graphics cards have a distinct enough purpose / function, I see no issues with using both, one at a time. If your monitor accepts multiple inputs, I'd take advantage of that, rather than use the KVM.

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I didn't know that KVM can spoil everything. And what do you meen by using one at a time, should I physically remove them or how can I control this process? – Nazariy Mar 22 '11 at 14:13
I realize I'm a little slow responding, but the method I'm using personally (good or not; you're the judge) is a monitor with two inputs. It is like a KVM, but the monitor is designed for it, and it doesn't add any (noisy) switches or cables. – Slartibartfast Mar 29 '11 at 4:27
Do you have to turn ON/OFF graphic card in order to prevent it doing extra job for no reason or windows is smart enough to do that on it's own? – Nazariy Mar 29 '11 at 16:25
I had a 4-input DVI-only KVM that seemed to noticeably reduce the frame rate of whatever I was looking at. – LawrenceC Sep 26 '12 at 14:26

Ok, I am running almost what you have suggested. I have a nVidia 560Ti and a Quadro 4600, obviously I can't run SLI, BUT, I set it up where my 560 is on PCIe 1 and the Quadro is on PCIe 2. Then I went into the nVidia control panel and put all my PhysX (3D rendering, etc.) on the Quadro. Works like a charm and my games are BEAUTIFUL. You DO NOT need a KVM, the others are right, it will make your screen blurry and it's an overall bad idea.

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Suggestion to run PhysX on a separate card is brilliant, going to try it out! – Philip Apr 16 '15 at 21:02

The technical answer is yes. The correct answer is no. KVMs are going to introduce video lag and fuzziness (digital KVMs are also pricey and have their own set of issues), and moving video cables around is going to be a pain. If you can hook up multiple inputs to your monitor that may be better, but you're then going to have to sort out your primary monitor any time you want to switch tasks from work to gaming.

You're better off buying a single card that will suit your needs. A Quadro is nothing more than a fancy consumer card, typically with special drivers and/or additional pipelines. I would investigate the Visual and Rendering software you're using and see what kind of performance you could expect to see out of a high end gaming card. For casual/personal use, you may be surprised, unless there is something that you're doing that specifically depends on the Quadro drivers or a particular feature of that card.

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I have already abandoned idea with KVM switch. I'm satisfied with Quadro FX performance in Adobe Suite. The main difference between FX and GTX series is BIOS and Drivers which make card cost 1000 USD more and does not allow to switch between two sets of instructions which seems to me possible for extra bucks. – Nazariy Mar 22 '11 at 15:03

Yes, you can do this.

But why you would want to have multiple graphics cards connected to a single monitor via a KVM is beyond me, because you won't get any additional productivity.

What you're doing by this is effectively purchasing two cars, a fast car and a slow car. You can EITHER use the fast car, OR you can use the slow car, but you can't use them both at the same time to make one really fast car.

If you want to do this, you need to use SLI, which requires:

  • Compatible Motherboard
  • Identical graphics cards
  • Compatible software
  • A pretty big budget
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Well they are not really slow and fast cards, they are both fast for their tasks, like SUV and Roadster. As I have seen that PhysX for example can chose between GPU and CPU for rendering. Why thay cannot work same way as sound cards for example? – Nazariy Mar 22 '11 at 4:35
@Nazariy - where's this talk about sound cards coming from? I don't understand what you're asking... you have two completely seperate video cards. These video cards cannot talk to each other unless you use SLI or CrossFire. You do not have SLI or CrossFire, thus the cards work independantly of each other. So you gain nothing by having them both hooked up to the same monitor. You're better off leaving just the fastest card in your system. – Mark Henderson Mar 22 '11 at 4:42
Sound cards, network cards, TV tuners you can install as many as your motherboard can handle. And they should work without bothering each other, as you can choose what to use for each task on application level. The main reason I need FX card because it perform much better than GTX in rendering. So it's quite hard to say which card is faster because they have different purpose. – Nazariy Mar 22 '11 at 14:44

Seeing that a 560 ti is 5 Generations newer than a Quadro FX 580 (GeForce 9 series family) I would just upgrade to the 560 and dump the Quadro card, any optimizations to the BIOS / drivers on the Quadro 580 can be overcome by other advancements in the family.

Thought I like the idea of using it for PhysX as said below, you would still rely on the 560 for graphics...

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It is possible but in practical terms only if the two video cards use the same video driver, that is, you cannot mix ATI/AMD video cards and Nvidia video cards in the same machine.

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I definitely have an AMD Radeon HD 6700 and a NVIDIA Quadro NVS 295 in my machine right now working perfectly together. This is also in a few other machines around the office. Maybe not SLI, or any dramatic improvements "working together", but definitely no issues of compatibility thus far. – Matt Sep 26 '12 at 14:58
two discrete video cards, or is one on-board (embedded)? – Jeff Atwood Sep 26 '12 at 20:07
Both, actually. I was talking about mine which is two discrete cards, but in another few machines we have onboard driving one monitor, and an add in ATI driving two more monitors. These are in Dell Precision 1500 and Optiplex 990 towers. – Matt Sep 27 '12 at 20:15

It sounds like you're really looking for a "Virtual Desktop" solution. These utilize APIs built into windows for creating multiple desktop spaces you can switch between. This will be a much more intuitive method for using one monitor for multiple workspaces on a single machine. It has been a while since I've used software like this, but it's very similar to the way Linux window managers provide multiple desktop spaces. Apparently the apps I used to use for this have faded out, but here are some I've found that might interest you:

EDIT Looks like there's a ton of them on CNET Downloads with good ratings and such.

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How does this help the OP with gaining more power for gaming? Based on the question, he would have two graphics cards and one monitor and switch between the cards depending on whether he was working or gaming. I do not see how a virtual desktop will help leverage different video signals. – MaQleod Oct 4 '12 at 19:48
The post was edited after my answer to clarify that the existing card was optimal for rendering; previously it sounded like he simply wanted 2 graphics cards in one machine hooked up to one monitor so he could switch between the two and I didn't see any reason he needed any more than the best of the 2 cards if the purpose was for separating gaming and workspace on a single machine. – TheXenocide Feb 8 '13 at 22:55
At least I think that's what happened; I could be wrong. – TheXenocide Feb 8 '13 at 22:56

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