MacRumors reports that the "available to ship" time estimates for Apple's (NASDAQ:AAPL) iMacs have lengthened to 3-5 business days, up from the usual 24-hours. The site also reports that shipping times for the 15-inch Retina MacBook Pro now range between 1-2 weeks.
Although MacRumors admits that these relatively long ship times might be "nothing more than regular stock fluctuations," the implication here is that Apple might be planning to launch updated models based on new Intel (NASDAQ:INTC) processors.
Is it too early for Broadwell?
The current iMac and 15-inch MacBook Pro laptops feature Intel Haswell processors built on the company's 22-nanometer manufacturing technology. Although Intel has launched the follow-on to Haswell, known as Broadwell, for very low-power systems such as the new MacBook and the MacBook Air, Intel has yet to release Broadwell for higher-performance all-in-one PCs and laptops.
Intel has said, though, that Broadwell-based processors aimed at those higher performance devices will launch at some point in "mid-2015." By Apple's definition of "mid-2015," this would imply sometime in the May to August timeframe.
Further, on Intel's most recent earnings call, CEO Brian Krzanich said that the ramp up of its 14-nanometer Broadwell products was "slightly ahead of [Intel's] forecast." It would hardly be a surprise if Intel has been shipping higher-performance Broadwell parts to Apple in order to support a launch of Broadwell-based iMacs and MacBook Pros.
Upgrades for the 21.5-inch iMac and 15-inch Retina MacBook Pro look likely
As far as the 15-inch Retina MacBook Pro goes, I'd expect that the Broadwell-based refresh will mainly consist of the new processor as well as the inclusion of Force Touch in the trackpad, as seen with the 13-inch Retina MacBook Pro.
The rumored specifications for the Broadwell-based Core i5-5675C/5675R and Core i7-5775C/5775R point to a slight CPU performance improvement over their Haswell-based counterparts. The integrated graphics processor, which Intel reportedly calls the Iris Pro 6200, should also be a decent boost from the prior generation Haswell chips.
This makes the move to Broadwell a no-brainer for the 21.5-inch iMacs. Further, if the Iris Pro 6200 offers a noticeable performance boost over the Iris Pro 5200 inside of the comparable Haswell chips, then Apple might eliminate the discrete GPU option for the highest-end 21.5-inch iMac.
The 27-inch question
Where the benefits from these Broadwell chips isn't so obvious are the 27-inch iMacs. I don't think Intel plans to launch any Broadwell-based processors that will be powerful enough to provide a performance boost from the current Haswell chips inside of the Retina 5K iMac; Apple's probably going to need to wait for Skylake to upgrade that.
For the non-Retina 5K 27-inch iMacs, the Broadwell value proposition isn't immediately obvious. The i5-5675C would be a good fit for the entry level 27-inch model. However, in the higher-end (but not Retina 5K) 27-inch iMacs, Apple uses either a 3.4GHz Core i5 with turbo boost to 3.8GHz or a 3.5GHz Core i7 that can turbo to 3.9GHz.
The highest end Broadwell -- the i7-5775C -- delivers 3.3GHz base clock with turbo to 3.7; the i5 model starts at 3.1GHz base and can turbo to 3.6GHz.
Since Intel claims that Broadwell is over 5% faster per-clock relative to Haswell, this means that the 5675C should be approximately equivalent to a Haswell running at 3.26GHz base and 3.78GHz turbo; for the 5775C, those values would be 3.46GHz and 3.885GHz, respectively.
Given that Skylake, which should be a true "upgrade" from Haswell on the CPU side of things, is just around the corner, I'm not sure if it's worth it for Apple to move to Broadwell. If it weren't for the 3-5 day shipping estimates for the 27-inch iMacs, I'd probably conclude that Apple will skip Broadwell and wait on Skylake for these products.