I agree with your estimation that Apple got a steep discount. But purchase prices and retail prices are two different stories.
There are
no retail prices for GPU chips. They are not sold that way. So this difference you are trying to point at is nonexistent in this case. Apple isn't buying cards from AMD they are buying components. Apple buys lots of components from a variety of folks ( e.g., VRAM for MBP's and iMacs ).
Maybe AMD did give a discount with the limitation that Apple may not sell the top configuration Mac Pro under a certain price point.
You are missing the blatant limitation that these GPUs sold will ONLY work inside of a 2013 Mac Pro. (OK maybe the next version, on the boneyard used parts market ). It is a embedded GPU. There is generally no sales market. Definitely not for new. Used is limited to cannibalizing a used Mac Pro for parts.
AMD has likely tacked on some licensing fee to use FirePro brand and some surcharge so that the BootCamp drivers work in Windows. Piled on top of the typical "OS X" mark-up these cards won't be AMD mainstream priced.
Just to make sure that the perceived value of the dual W9000 setup is comparable to the prices of dual W9000 workstations of other vendors.
AMD doesn't sell very many W9000's. Most of the workstation system vendors don't carry it. Perceived value isn't doing much good for AMD if almost nobody buys them. Far more likely Apple is going to sell more W9000 equivalent cards than any other system vendor that AMD currently has signed up to sell them.
Because if Apple would sell their nMP several thousand dollars below HP, Dell and other ... this would put price pressure on AMD Firepro brand.
How? Does the W5000 put price pressure on the brand? The mobile cards put pressure on the brand? It doesn't put pressure on the overall brand at all to have a range of price points.
For the individual FirePro cards it isn't new pressure either. The GPU chip itself is largely the same as the mainstream AMD cards. There are differences in VRAM , drivers , and on some versions ECC but there is already "Not buying going cheaper" pressure on FirePro already.
For HP, Dell, etc workstation users they can not use the Apple card. So it isn't an option. They would have to dump their whole workstation and buy a whole Mac Pro to get these more affordable FirePro "cards". Far more likely those folks are wedded to various PCI-e cards , internal bulk storage , etc. that will segment them. Those who were only buying a classic form factor
solely to get a FirePro card and have a completely OS independent software base is likely small.
So I guess, AMD will rather give Apple a huge profit margin than devaluate their brand.
B.S. If AMD mandated a huge profit margin they would take a huge share of it themselves. They wouldn't "give" it away. What is highly dubious is that these huge profit margins only really matter if actually
SELL the card. AMD's share of the Pro card market has been slipping over the last couple of years.
Rather than devalue this is far more likely a way for AMD to pump up its deployed unit volume presence without having to lower its standard form factor PCI-e cards prices much at all. AMD gets higher volume sold and still makes much higher than Apple margins on the standard PCI-e cards they still do sell.
The Mac Pro "after market" add-in card market dropping to zero is not a major problem for either AMD or Nvidia.
If AMD wanted to do something smart they'd have Apple pay for FirePro tagged GPU chips with VRAM. Apple uses its higher buying power to get cheaper VRAM and pass that along to AMD. AMD then uses that lower VRAM to boost the already sky high margins on the standard FirePro cards they do sell.
Call this huge profit margin that AMD hands over to Apple an advertisement payment for the Firepro.
First, it is highly doubtful that Apple is going to take the much higher than corporate standard profit margin. Apple is going to take less money, so it won't be profit. AMD gets less money but they also don't have to take any risk (or expense ) in selling the whole card.
Second, it is a different market segment. Your assumption is that some significant wave of Windows/Linux workstation owners are going to shift over to the Mac Pro. Not going to happen.
Lower FirePro card prices are largely going to help the new Mac Pro tread water the number of Mac Pros sold. A minority subset of current Mac Pro folks who require dual CPU package set ups are actually going to increase the number of HP, Dell, etc workstations sold. Similarly some users will have preferred a single GPU. Dual normal FirePro priced cards would also drive many of those folks to HP, Dell, etc. also.
So sure they may peel a small few off mainstream workstation sales but they are also going to loose folks to mainstream workstation sales. If more people flee AMD has a bigger opportunity to make even higher money by directly selling them the standard FirePro card. If an even swap then again AMD loses nothing. Even if there happens to be a small net shift to Mac Pro ... again AMD gets higher volume. Those are also sales not going to Nvidia and AMD's Pro market standing goes up. Again AMD wins.
The design choice to make dual GPUs standard means the far higher than Apple mark up must be shaved off the cards to make the overall system a viable product.