GPUs for Early 2008 Mac Pro

Essence_of_War

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I'm thinking about buying my gf a new gpu for her mac pro so that she can upgrade to ML/Mavericks (there is a video playback problem with the original gpu, I believe a radeon 2600, under ML), and also so that she has access to some additional display options.

I know that the Radeon 5770/5870 are options, and that there exists special mac versions of the 7950 and 680 that will work as well. Unfortunately, these special mac versions are quite a bit more expensive than ordinary versions of the same cards.

My understanding is that OS X has drivers for all (or nearly all) of the available video cards, so is there anyway to use ordinary gpus with the mac pro without having to shell out extra for the special "mac versions"?
 

TheStu

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nVidia has OS X drivers for later OS versions (10.7+ I think), and I read somewhere about a guy that got a GTX 670 working OOB with little to no effort.
 

Essence_of_War

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A little googling...was it this guy by chance?

http://junipermonkeys.com/putting-a-geforce-gtx-670-in-a-mac-pro

What I'm gleaning from this is that any gpu with OS X drivers can be used, you just won't get the grey boot screen. Is there any reason that I'd need that screen? I assume that might be where I'd see options like "boot from different media" or something like that, since the video drivers won't load until OS X loads.
 

TheStu

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A little googling...was it this guy by chance?

http://junipermonkeys.com/putting-a-geforce-gtx-670-in-a-mac-pro

What I'm gleaning from this is that any gpu with OS X drivers can be used, you just won't get the grey boot screen. Is there any reason that I'd need that screen? I assume that might be where I'd see options like "boot from different media" or something like that, since the video drivers won't load until OS X loads.

Basically, yes, that's the EFI boot screen. If for some reason you wanted to boot into Windows, you could do that through system preferences, or if there's a larger problem drop the old card back in.
 

vailr

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There's a possible work-around via update flashing a regular PC video card's bios to a Mac version bios. However, standard PC video cards of the same general model number often have a smaller bios size. So: careful investigation of the video card's bios size would be needed before purchase.
 

Essence_of_War

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OK. So, assuming that for whatever reason I don't care about the EFI boot screen (for example, I'll keep the old card around in case of a problem) then it sounds like it's just a matter of:

1) Picking a card with drivers that OS X Mtn Lion supports
2) Powering the card.

I think I can handle 1).

Assuming I'm using a PC GPU that has 6/6+2 pin connectors, how do I get power to the card from the Mac PSU? Does it use the same type of connectors?
 

TheStu

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OK. So, assuming that for whatever reason I don't care about the EFI boot screen (for example, I'll keep the old card around in case of a problem) then it sounds like it's just a matter of:

1) Picking a card with drivers that OS X Mtn Lion supports
2) Powering the card.

I think I can handle 1).

Assuming I'm using a PC GPU that has 6/6+2 pin connectors, how do I get power to the card from the Mac PSU? Does it use the same type of connectors?

Yes, the Mac Pro PSU should have the connectors you need, it's designed to accommodate up to 4 GPUs after all.
 

Essence_of_War

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OK.

So I guess they're either in the case attached to the current GPU, or they might be out of the case and stored separately. I'll look into this tonight.
 

TheStu

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OK.

So I guess they're either in the case attached to the current GPU, or they might be out of the case and stored separately. I'll look into this tonight.

Yea, just crack the sucker open. I don't think the PSU is modular, so they would be in there somewhere
 

slashbinslashbash

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In my 2006 Mac Pro, the extra header for the video card power is actually on the motherboard. The video card comes with a specific cord to connect to it. (All the Mac Pro specific video cards came with one.... there are folks on eBay who sell just the cables themselves.) Not sure if it's the same with the 2008 models.

Pretty sure this is the one: http://www.ebay.com/itm/Apple-Mac-P...S_Power_Cables_Connectors&hash=item35c914b773
 

TheStu

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In my 2006 Mac Pro, the extra header for the video card power is actually on the motherboard. The video card comes with a specific cord to connect to it. (All the Mac Pro specific video cards came with one.... there are folks on eBay who sell just the cables themselves.) Not sure if it's the same with the 2008 models.

Pretty sure this is the one: http://www.ebay.com/itm/Apple-Mac-P...S_Power_Cables_Connectors&hash=item35c914b773

That would solve the cable tidiness issue I suppose.
 

Essence_of_War

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The power headers are on the MoBo, and it looks like I'll need small-6-pin to normal-sized-6-pin cables to use them. The PSU doesn't appear to have them.

Also, yesterday I helped my GF install a 7950 Mac Edition into her work Mac Pro (2009) and it went swimmingly. Resolved the video-playback stuttering issues she had had when she tried to upgrade to Mtn Lion in Feb which required her to downgrade back to Snow Leopard.

I was able to confirm that latest Mtn Lion has the 7950 drivers as the driver CD that came with the 7950 told me I didn't have to install them.

The question is now is there a way to dodge the boot screen issue. I see a few options, one of which is attempting to flash a card myself. Does anyone know of any good resources to read about how-to-do that?
 

Essence_of_War

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Additional option.

Right now she's only using the PCI slots for a single bus-powered GPU. So could I leave the current gpu in, add a 2nd gpu w/o mac firmware but that does have drivers and is known to resolve the stuttered playback-video-problem, and connect one output from each video card to one of her monitors?

This way, if she needed the grey boot screen for anything, she could just switch monitor inputs to get to it without any hassle, and normally she'd just leave it selected for the newer card.

Does that sound like it would work?
 

Essence_of_War

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Hey folks, thought I'd give a follow-up/success story!

I ended picking up a dual-fan sapphire 7950 and just popped it in. I picked up a 6pin-minipci power cable -> 2x normal 6pin PCI power cable to drive it, and updated to the latest OS X (I think 10.8.3) before installing the card to be sure that I had drivers.

I don't get a boot screen when I hook the displays up to it (obvs) but everything is hunky-dory otherwise, and there is no stuttering in the video playback!

I put the original GPU (Radeon 2600! :awe:) into another open slot and can get a boot screen by switching display inputs to that. It's a relatively minor extra step, but since there was an open PCI slot, I prefer this solution to paying an extra $200-250 for the mac edition.