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Warhaven · Mar 29, 2011, 01:32 PM

I was wondering if anybody had any news or links to information on this. I'm curious if the reason we haven't seen Crossfire or SLI on Macs is because of AMD & NVidia not caring, or Apple having a stick up their butt (as is often the case), incompatible hardware, or a combination of the listed items. I haven't found anything in Google discussing this in detail as to who is at fault here, so hopefully someone here has some useful info.

Thanks.

residentEvil · Mar 29, 2011, 02:01 PM

here you go:

Does the Mac Pro support standard PC video cards? Does it support SLI or Crossfire? @ EveryMac.com

olePigeon · Mar 29, 2011, 02:12 PM

Summary: AMD and nVidia have no plans on writing CrossFire or SLI supported drivers or firmware for OS X.

However, AMD did write CrossFire supported drivers for Linux because... well... I don't know why. Linux gaming market is even smaller than OS X.

Warhaven · Mar 29, 2011, 02:18 PM

Originally Posted by residentEvil

here you go:

Does the Mac Pro support standard PC video cards? Does it support SLI or Crossfire? @ EveryMac.com

Yeah, but doesn't say why. Is it lack of interest in the Mac platform? Is it Apple being difficult by not providing access to APIs the companies need? Or... what?

Now that I think of it, it can't be a hardware limitation, since you can Crossfire under Windows. So it must be an AMD or Apple thing (or both).

reader50 · Mar 29, 2011, 02:31 PM

Write the editors at Inside Mac Games. They can sometimes get answers out of manufacturers or Apple. You could also ask Rob at barefeats. I've contacted him a few times over the years - he always replies promptly.

mattyb · Mar 30, 2011, 06:45 AM

I would have thought that due to the increase in game sales on consoles that less and less people are thinking of the Mac (in particular OS X) as a gaming platform. iOS is another matter.

Big Mac · Mar 30, 2011, 08:07 AM

Yeah, but developers have been taking notice of increased Mac sales. Valve really showed it cares about Mac gaming by porting over Steam. I think the real issue is that serious gamers want a Mac that doesn't exist: the xMac. I've also read that the Mac Pro's PSUs aren't beefy enough to support their native hardware plus two top of the line GPUs, so it really limits the SLI/Crossfire appeal on the platform when there's only one Mac model that has GPU flexibility and even it is very limited. (I could hardly believe it when I read that because I always assumed Mac Pros had really strong power supplies, but multiple people have confirmed they're not suited for multi-high-end GPU configurations.)

sek929 · Mar 30, 2011, 09:02 AM

If Valve thinks the OSX platform is worth it to develop for then something must be going right for Mac gaming.

P · Mar 30, 2011, 09:36 AM

Valve has also managed to get Apple to update graphics drivers and OpenGL implementation to fix many long-standing bugs. I know that 10.6.7 has issues with the 320M, but it certainly improved performance on my Radeon 4850.

If Apple wants better support for gaming on the Mac, they need to make MBPs with top-of-the-line mobile graphics. Gaming laptops are big business and command huge premiums, and the 17" at least is big enough for the cooling required. "6750" sounds like it's a great chip, but there are 7 models above it from AMD alone. There isn't even a logistics cost - just take the cards you shove into the iMacs anyway and make them an option in the MBP.

Of course there is absolutely no indication that AAA Mac gaming even registers on Apple's radar, so I don't think it will happen, but it's easy enough and could net them some real profits if done right.

Leonard · Mar 30, 2011, 10:22 AM

Originally Posted by Big Mac

I've also read that the Mac Pro's PSUs aren't beefy enough to support their native hardware plus two top of the line GPUs, so it really limits the SLI/Crossfire appeal on the platform when there's only one Mac model that has GPU flexibility and even it is very limited.

That's not true. The power supply in the Mac Pro's is more than powerful enough. The problem is likely that power connections aren't as easy to come by. The Mac Pro has power connections, I believe for one high-end GPU, but not two. For a second GPU, you would have to split power connections from an optical drive or HD.

As someone has said above, the hardware is not the problem, SLI has been done on the Mac Pro in windows.

But you are right that a Mac Pro isn't a reasonably priced gaming machine.

P · Mar 30, 2011, 11:43 AM

Originally Posted by Leonard

For a second GPU, you would have to split power connections from an optical drive or HD.

Power connectors which are not easy to get to, as the HDs are docked, and anyway you'd need a SATA power to PCIe power adapter. Those are not as common as the ones from 4-pin molex, but I'm sure they exist.

The old PowerMac G5s had ginormous PSUs - 1100 W was the peak, IIRC - but the recent Mac Pros are smaller.