Does an APU becomes a standard CPU when it is combined with a discrete GPU?

Nielo TM

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No one can deny the A10-7850K is heck of a processor as it is capable of 855.68 GFLOPS (faster than i7-4770K and retails at half the price). But what happens when a discreet GPU (e.g. R9 290) is added to the mix? Does the GPU core on the APU gets completely disabled? Or does it continues to function, but only processing compute tasks?


PS: I apologize if this question has been answered before.
 
You have to get the right one to get AMD dual graphics working and they still haven't gotten all the bugs out of it.
 
I know it can be "crossfired" with a discreet AMD GPU that is similar in performance. But I'm referring to high-end and nVIDIA GPUs.

What happens to an APU when a user decides to install R9 290/X or GTX 780/Ti?
 
No one can deny the A10-7850K is heck of a processor as it is capable of 855.68 GFLOPS (faster than i7-4770K and retails at half the price).
Yeah, that shouldn't be the one spec or even sole criteria you should be looking at when comparing CPUs. Read actual performance reviews.
But what happens when a discreet GPU (e.g. R9 290) is added to the mix? Does the GPU core on the APU gets completely disabled?

Or does it continues to function, but only processing compute tasks?
Depends on how you setup the UEFI. You can set it so that the onboard GPU is disabled when a discrete is added. You can also set it so that both the onboard and discrete can be active at the same time, each powering a different monitor.

With that said, adding a high-end discrete GPU to a APU effectively negates the APU's chief advantage over Intel CPUs: The significantly faster onboard GPU. So unless you're planning on playing nothing but Mantle-enabled games, I generally would not recommend pairing an APU with any sort of high-end GPU.
 
I'm not looking to upgrade as I've already upgraded my system last year. (see sig). I'm just interested in APUs (from a technology perspective). There's very little information on how an APU would function with high-end GPUs.

Since there are only disable and "crossfire" options in UEFI, I'm guessing APUs won't remain APUs once a high-end GPU is added to the system, no?
 
Since there are only disable and "crossfire" options in UEFI, I'm guessing APUs won't remain APUs once a high-end GPU is added to the system, no?
They'll still remain APUs even when a high-end GPU is added. Just APUs with graphics portion not being used.
 
Got it. So HSA and hUMA will continue to function despite the configuration? Just want to be absolutely certain on this. If you have any links to resources that explains various configurations, I would appreciate it.


Side Note: I'm guessing Hanswell doesn't work the same way...or does it? It is sort of an APU after all. It has a GP-GPU core and zero-copy unified memory.
 
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Say you add in a 290x, the R7 on the APU is still active and used for HSA, the R7 is also used for physic instead of the 290x.

The R7 is also used for decoding media instead of the 290x as it would be a wast to use the 290x for that sort of work.

So normally the 290x would do graphics, physics and decoding, but now the 290x would only do graphics.

Haswell doesn't work like an APU, it works like a CPU with a GPU plugged in, although Intel is putting a lot of work into making their GPUs faster (IRIS) so I can see them releasing an APU in the future that has HSA, HSA is open like AMD64 so it wouldn't be the first time they have adopted open AMD standards.
 
Excellent! Thanks for the info. I suppose Intel has to join the HSA foundation sooner or later considering all major players are on-board. Need to dig up some info regarding Hanswell vs Kaveri. They seem similar, but they are also very different. It's so difficult get in depth info for some reason.
 
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Sorry it was due to auto correct. SwiftKey still hasn't picked it up yet.

PS: I've updated my last post.
 
Accessing system ram

7850k

iGPU > Memory Controller > Memory > Memory Controller > iGPU

4770k

iGPU > CPU > Memory Controller > Memory > Memory Controller > CPU > iGPU
 
You can run things separately on the little GPU embedded in the Intel CPU. They have a function called QuickSync. Streamers on Twitch can use it to render up to 1080p video @30Hz to lessen the load on the CPU. It's not powerful enough to do more than that. I render 1080p @60Hz in OpenCL on my HD7950 without a problem using OBS.
 
I was under the impression that GPU encoding is inferior to CPU encoding in terms of image quality; and the only way to boost speed while maintaining quality is via HSA-hUMA based APU (since both the GPU and CPU can simultaneously process the video).
 
QuickSync works fine for quick and dirty encodes. Just know that you are trading quality for speed.
 
Here's a PDF from 2012 that goes into detail about how APU's can function when paired up with higher-end discreet GPU's in games: Link
 
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