How to enable Hybrid Crossfire

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FiZuR

Limp Gawd
Joined
Aug 29, 2005
Messages
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I can not get my hybrid crossfire to enable. I have vista ultimate with sp1 installed and using the latest ati drivers. Am i supposed to have my monitor plugged into the onboard video or my 4850? Do i need to install drivers for the IGP as well?
 
Only lower end cards will run hybrid crossfire. 4850 is certainly not low end.
 
It would be nice to be able to utilize the onboard video regardless of the power of your add in card.
 
FiZuR said:
It would be nice to be able to utilize the on-board video regardless of the power of your add in card.
Click to expand...

This cannot be done for a simple reason: keeping the frames synchronized would be impossible.

Imagine you actually did this, and hooked up a GPU 10x more powerful in Hybrid CF with on-board video. Say you ran at a high resolution, because the discrete card can handle it. At this resolution, your discrete card generates 60fps.

The on-board video would render at a frame rate 1/10 that, or 6fps. This would limit your maximum frame rate to 12fps, assuming you used alternate frame rendering. This happens because every other frame has to be synchronized in AFR. This yields a slowdown for your dedicated GPU's 60fps rendering speed.

No, it is not really possible to get around this, because the on-board GPU would have to know what the frame would look like 10 frames in-advance. The game engine can't give the card that kind of information.

Pairing two similar GPUs makes this synchronization a lot easier and more beneficial. The fact is, with AFR rendering you can only DOUBLE the performance of your slowest component.
 
I just want the onboard video to run windows while shutting down the pcie card
and when I start a game I want to PCIe to turn off and onboard off, shouldn't be too hard.
 
This is getting frustrating, reading different things on different sites. Some reviewers say 790GX does not support the on-board graphics shutting down discrete graphics when not in 3d.

BUT from the Foxconn site:
ATI Hybrid Graphics technology automatically boosts graphics performance by enabling both the discrete graphics and integrated graphics card to render simultaneously. When less graphics intensive applications are running, the system can disable the installed graphics card, thereby saving energy.

http://www.foxconnchannel.com/news/news_detail.aspx?ID=en-us0000223

Guess I'll find out when my board arrives but several review sites and it SEEMS AMD is saying NOT.
 
defaultluser said:
This cannot be done for a simple reason: keeping the frames synchronized would be impossible.
Click to expand...
Am I reading this incorrectly, or isn't this what nVidia's already doing with their hybrid SLi? The list of cards compatible with their "Hybrid Power" tech certainly isn't limited to cards of the same class as their IGP.

If nVidia's already doing it, I had assumed that Hybrid CrossFire was similar enough to have the same feature enabled? Unless I'm reading it correctly that you have to plug your monitor into one or the other graphics sources? If that's the case, I'd certainly be willing to do that if it meant dynamically powering the discrete card...
 
t-readyroc said:
Am I reading this incorrectly, or isn't this what nVidia's already doing with their hybrid SLi? The list of cards compatible with their "Hybrid Power" tech certainly isn't limited to cards of the same class as their IGP.

If nVidia's already doing it, I had assumed that Hybrid CrossFire was similar enough to have the same feature enabled? Unless I'm reading it correctly that you have to plug your monitor into one or the other graphics sources? If that's the case, I'd certainly be willing to do that if it meant dynamically powering the discrete card...
Click to expand...

I think you're confused. Hybrid Crossfire is ATI's equivalent to Nvidia's GeForce Boost. ATI has no equivalent to Nvidia's HybridPower.

Hybrid Crossfire saves power by disabling the discrete GPU at idle and enabling Crossfire in games.

HybridPower saves power by disabling the discrete GPU at idle. The Discrete GPU is enabled for games, and the on-board GPU is used as a forwarded frame buffer: every frame rendered by the discrete GPU is copied over the PCIe bus so it can be displayed by the on-board GPU.

You thread at AMD yielded no answer because you asked the wrong question. Hybrid Crossfire will never get a larger compatibility list, for the reasons I posted above. What you want to ask is: does AMD have a competitor for Nvidia HybridPower in the works?
 
defaultluser said:
You thread at AMD yielded no answer because you asked the wrong question. Hybrid Crossfire will never get a larger compatibility list, for the reasons I posted above. What you want to ask is: does AMD have a competitor for Nvidia HybridPower in the works?
Click to expand...

Nah, I'm not confused. I updated the AMD thread last night with just such a question. I assumed, though, that Hybrid SLi & Hybrid Power are two technologies that can't be separated (along with Hybrid CrossFire & the as-of-yet-non-existant Hybrid Power); or is that incorrect?
 
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