TI would think two W5000s make the most sense for the low end and W7000s in there too based on how things are priced. .....
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Because the price of these cards is completely unknown, an entry level GPU is also unknown. I suppose it is likely that a W5000 is a reasonable entry,
The W5000 is quite doubtful. I think that is being driven by looking at AMD's retail prices for FirePro cards and then trying to fit to the "classic" $2,299-2,499 range of pricing. If so, I suspect that is a huge mistake.
The W5000 is rather weak. For example the GPU in the top standard configuration iMac is a GT675MX ( there is a GT680MX BTO option that is better than this). While capable of 4GB Apple only used 1GB VRAM in the iMac ( 2GB in the BTO ), but basic stats:
19 Gpixels/s 48 GTextures/s 115 GB/s memory bandwidth 1152 GFLOPs.
Where as the W5000 is just :
26 Gpixels/s 39 GTextures/s 102 GB/s memory bandwidth 1267 GFLOPs
Note that the GT675MX is a
mobile GPU; not a desktop one. So Apple is going to put two upper mobile level performance GPUs in a Mac Pro and sell it at $2,000+ price points and that is going to be competitive? I don't think so.
Never mind a GT680MX and top end BTO iMac that will blow right past this on graphics performance probably around the exact same price point. Again it isn't just other WinPC workstation, that isn't particularly competitive with the BTO iMac.
I highly doubt there is going to be any Crossfire available to try to gap these iMacs. ( So the whole they're slow but if bound them together it is OK performance isn't going to fly).
The other major problem with the W5000 is that it is limited to a 2GB VRAM cap. Again this is a chuckle when the mobile GPUs in the iMac have possible 4GB VRAM caps. The GPGPU that is pragmatically being tagged for a significant amount of GPGPU work needs more space to be more competitive.
The W5000 only makes sense in the distorted funhouse mirror pricing context of the rest of the FirePro line-up's prices. Outside of that context, it is nonesense. It is a sub $100 GPU card that belongs in generic white box rectangles with slots. There is nothing particularly upscale performance at all about the performance relative to modern GPUs.
That said, we also don't know if Apple will allow users to buy a Mac Pro with say one W5000 and one W9000, or some other combination.
Not going to happen with 3 Thunderbolt controllers and a HDMI output . Pragmatically need two GPUs to make this machine effective. Nevermind the needs for computational headroom while concurrently driving some dynamic content on a 4K screen. The machine is above average price. It still needs to be useful 2-3 years from now. Apple doesn't particularl want folks to squat on a Mac Pro for 6-10 years but they also know folks are not going to churn them every 1-2 years either.
It W= is a $400 HD7970 with ECC VRAM, and an 800% mark-up (at least as far as I can tell).
I think you are grossly underestimating how much GDDR5 RAM costs at the speeds needed and in ECC format. It isn't all of it but it is a larger BOM cost that significantly lowers that "mark-up" .
AMDs FirePro series are not particularly competitively priced for the level of real performance can eek out with the AMD drivers and infrastructure. If AMDs mark-up is 80-100% and Apple can walk them down to 20% then starting with two W7000 would make sense.
The W8000 would make sense also as a middle of the line-up card if its prices were grossly distorted too. Both the W8000 and W9000 take ECC GDDR5 VRAM. Given Apple's modus operandi of make the most use of common parts across products it would make alot of sense to two very slightly varying cards on these two to form the top-middle end of the line up.
The W7000 is actually a bit of an oddball in that it is non ECC. That may be necessary at this point to limbo in at the entry level's Mac price point. Although I wouldn't be surprised if the entry card might be a W8000 gimped a bit on VRAM if Apple can detach the GPU package from AMD's misguided mark-up.