Does 2 x ATI HD 5770 make a difference in FCPX?

[wildgiles]

Just wondering if anyone has 2 x apple ATI HD 5770's in their mac pro and running FCP X if it makes any differences in exporting unrendered project timelines. Apple says FCP X is really great at using graphics cards, I'm wondering if having 2 5570's is better than 1 5870 for FCP X

[CaptainChunk]

Originally Posted by wildgiles

Just wondering if anyone has 2 x apple ATI HD 5770's in their mac pro and running FCP X if it makes any differences in exporting unrendered project timelines. Apple says FCP X is really great at using graphics cards, I'm wondering if having 2 5570's is better than 1 5870 for FCP X

I'm pretty sure that FCP X's OpenCL acceleration only works with one GPU. Even if it did work with two GPUs, a single 5870 would outperform a pair of 5770s. At least this is the case with Crossfired 5770s in Windows.

If you wanted faster, you'd want a 5870.

[wildgiles]

Dang, oh well. It's interesting that Davinci Resolve scales it's performance almost directly to the # of video cards you have.

[LethalWolfe]

Resolve was designed for people where price was not a primary consideration while FCPX was designed to run on an off-the-shelf Mac. While it would be nice if FCPX scaled up w/multiple GPUs I wonder how often that feature would be taken advantage of.


Lethal

[cgbier]

And if you aim at DaVinci, then you should use a headless nVidia Quadro as a second GPU.

[Erendiox]

Davinci doesn't really scale to the number of GPUs quite like you're describing. What it will do is use a single GPU solely for acceleration, and then a second GPU for the GUI and general computing. In this way, you can take advantage of having two GPUs running simultaneously.

[wildgiles]

They might sell graphics cards if FCP X advertised that it could use them. That would be a win win situation for mac pro users like me and apple. I hear that the 5870 is 20% faster than a 5770 ofr rendering in FCPX. My theory is that if FCPX could in fact use two cards would you not get 100% faster performance with renders.

[LethalWolfe]

Originally Posted by Erendiox

Davinci doesn't really scale to the number of GPUs quite like you're describing. What it will do is use a single GPU solely for acceleration, and then a second GPU for the GUI and general computing. In this way, you can take advantage of having two GPUs running simultaneously.

That's how it tops out on Macs because of the limited PCIe slots. If you use a qualified PCIe extender box with a Mac or a PC tower w/more PCIe slots you can shove 4 GPUs into the mix (possibly more, not sure) and Resolve will utilize them. 4 GPUs is the recommend number by Blackmagic to really take advantage of what Resolve can do.

You can also hook Resolve up to a render farm but I'm not sure what all goes in to doing that.


Lethal

[Erendiox]

Originally Posted by LethalWolfe

That's how it tops out on Macs because of the limited PCIe slots. If you use a qualified PCIe extender box with a Mac or a PC tower w/more PCIe slots you can shove 4 GPUs into the mix (possibly more, not sure) and Resolve will utilize them. 4 GPUs is the recommend number by Blackmagic to really take advantage of what Resolve can do.

Lethal

Really now, I didn't know that. Thank you for the info. I'll have to look into it.

[cgbier]

Originally Posted by wildgiles

They might sell graphics cards if FCP X advertised that it could use them. That would be a win win situation for mac pro users like me and apple. I hear that the 5870 is 20% faster than a 5770 ofr rendering in FCPX. My theory is that if FCPX could in fact use two cards would you not get 100% faster performance with renders.

You won't. The main work is still done by the CPU. The GPU has only a supporting role. If you really want to have faster render speeds, you'll need to build a render farm with a bunch of Macs and Q-Master.

75% of all Macs sold are laptops, and as Apple wants to bring FCP X to the masses, they keep the hardware requirements pretty low (as does Autodesk with its new Smoke). A pretty nice move, I'd say.