virtualbox.org

Hey all,

So I am the (lucky) owner of both a Mac, and Photoshop for Windows. That makes Virtual Box the perfect tool - I already have a 64-bit (like my Mac) W7 VM.
Now, Photoshop could use my GPU - yet VB seemingly can't handle that ... So Photoshop says "Nope, you ain't got any GPU." But I actually have two (like any MacBook Pro from 2011) : a low-consumption one (integrated Intel HD Graphics 3000), and a powerful one (AMD Radeon HD 6750M via PCIe). I use VB 4.3.6 r91406.
Any suggestions ? Probably a driver or plugin ?
Other VB users recommend PCI passthrough, but they're talking about Linux. Is it available and efficient for Mac ?

Thanks in advance for your help,

Charles

A VM runs on emulated hardware, and the VBox emulation doesn't include a GPU.

Install the GAs to get faster graphics, though I won't promise that'll make Photoshop any happier.

Done that already - before even installing Photoshop on my VM.

Let me reiterate what mpack said:
Your virtual machine is using virtual hardware, including virtual graphics card which is not as powerful as an actual graphics card. Programs like Photoshop tend to push the physical hardware to their limit. Applications that have high requirements on the GPU (drawing, 3D, games) are expected to not work as good as on the real hardware, if they work at all.

Thank you for the clarification. I understand now how it theoretically is.
But, one question :the graphical workload can still be redirected by VB to the GPU, as requested by the guest OS (and whatever app it's running), right ? Now, there has to be a cost to that redirection algorithm, but I'm hoping it would still be worth the while.

Yes, if you install the GAs, with 3D acceleration, then 3D ops in the guest are actually executed in the hosts OpenGL library, which usually map to GPU calls though that obviously depends on the library.

What the guest software can't ever do is use or sense the GPU directly. And, if it insists, then you can't use it in a VM.