Apple Shares New Support Document Addressing Distorted Screen Issue on Macs Running Windows 10

__Question__

If macOS automatic graphics switching is currently using integrated GPU, does it still use the dedicated AMD graphics memory?

For me, the system info shows two sets of graphics memories, I am confused as to when either is used and how they transition between memories if any.

Radeon Pro 560X 4 GB
Intel UHD Graphics 630 1536 MB

The Intel chip does not have its own dedicated memory. The 1536MB listed is part of the main system memory that can dynamically be allocated or deallocated as video memory. The video memory in the dGPU will only be used when it is active or if an application specifically uses it. You can programmatically control where the memory is stored so in part it's up to the developer. In theory I could write a program that runs on the dGPU but stores everything in main memory... It'd be slow but can be done. - The iGPU does not have access to the dGPU's VRAM, only system memory, but the dGPU has access to both its own and system memory.
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One of the many reasons I don’t use Windows any more. Shouldn’t windows update the driver itself, or god forbid, do a systems check before installing? I can’t begin to count the times when the installer would almost complete and then go “oops, found a problem”. So many hours wasted over the years

I'm a huge Apple person, and don't like using Windows myself, but this isn't Windows' fault. This is on Apple. AMD has shipped drivers and Windows does automatically install them... But not on Bootcamp Macs where Apple wants to be in control of the driver situation and ship their Bootcamp driver packages rather than just using AMD generic drivers.
Hence why there is bootcampdrivers.com

One of the many reasons I don’t use Windows any more. Shouldn’t windows update the driver itself, or god forbid, do a systems check before installing? I can’t begin to count the times when the installer would almost complete and then go “oops, found a problem”. So many hours wasted over the years

Nice try. This has very little to do with Windows, as Apple controls the driver situation on a bootcamp install as well.

A potential proper workaround to this situation is to visit bootcampdrivers.com ; it's one guy who essentially takes the latest AMD drivers and works to make them compatible with W10 installed on BootCamp, rather than relying on Apple's archaic GPU drivers for Windows.

More importantly what people should be asking is: why doesn't Apple just let the part manufacturer produce their own driver, as they are already equipped to do? AMD and NVIDIA are much, much better at making drivers for their display adapters.

"Recovery: use a real operating system"

I don’t know what your job is but in my line of work you need Windows to get things done. At some point we had to use virtual machines on Mac and everything was so slow it was frustrating.

For academic tasks we use mostly Linux, for professional Engineering is Windows hands down. For gaming Windows wins as well.

Shouldn’t windows update the driver itself, or god forbid, do a systems check before installing?

Don't blame MS on this, Apple is the one who's producing the drivers, I've always had issues with apple drivers in windows, Apple's track record of supporting windows is rather low. I understand why, they want Mac owners to use MacOS as that's where Apple will make their money, as that keeps them in the ecosystem.

Thank you for your thorough explanation. So, when macOS RAM pressure is high, even when graphics demand is within the capability of the iGPU, it would still be beneficial to turn off automatic graphics switching and let macOS to use dGPU exclusively to take advantage of the dedicated VRAM, right? As that isn't a part of the system memory.

I actually imagine that even when the dGPU is active, Apple also tries to keep all display resources in system memory such that when you do switch back to the iGPU it can do the switch fast and fluently.
I don’t know for certain though, but I’d imagine Apple’s automatic switching system does take things like memory load into account for how to handle things. It’s also worth noting that while it may say you have 1536MB for video memory, it’s actually rather dynamic, and if you’re not chugging games or other high VRAM using tasks at it, it’ll dedicate less to VRAM and more to general system memory.

I don’t think it’d make a big difference, if any at all, to be toggling GPU switching just to try and free system memory. I don’t think it’d actually free it anyway, and if it does it probably only does so by pushing it to compressed pages, which still uses RAM. Otherwise I think the time it’d take to switch back to the iGPU when necessary would be too long for Apple to consider acceptable.

Parallels desktop.

https://www.parallels.com/landingpage/pd/general/?gclid=EAIaIQobChMIsMH3n9yv6AIVlv_jBx1Qgw_nEAYYASABEgLkyfD_BwE