As we approach WWDC, which kicks off on Monday, rumours are hotting up about the Mac Pro. Some reports claim that the new professional Mac will make an appearance at the show, while others suggest that it's not going to launch until this autumn.

Those predicting a new Mac Pro at WWDC point to retail shortages of the Mac Pro. MacTrasts claims that a survey of Apple resellers and the companies website showed "a remarkable shortage of Apple’s entry-level Mac Pro".

That report claims the majority of stores were out of stock or had limited supplies of the 2012 Mac Pro.

In the UK and Europe the Mac Pro cannot even be sold as it no longer complies with health and safety regulations.

The shortage of Mac Pro may not actually indicate a new model is on the way. Our own reseller contacts told us before the removal of the Mac Pro from sale that they rarely stocked the units due to the space requirements.

However, Lou Borella, the creator of the Facebook group ‘We Want a New Macpro,’ claims a "credible" source has told him not to expect a new Mac Pro until this autumn.

The autumn shipping date for the new Mac Pro was one of a number of snippets of information that the source shared with Borella. Other insight provided about the new Mac Pro included:  

  • It will be heavily reliant on Thunderbolt
  • There will be no internal expandability
  • It will have support for dual GPUs with three-monitor support right out of the box
  • No Firewire 800 or optical drive
  • It will be a completely new design

Storage options in the new Mac Pro

Analysing these snippets of information, Borella writes that the optical drive will be no surprise to anyone. However, he notes that if no internal expandability means that there will be no hard drive bays "I'll be pretty upset." He suggests that as an alternative Apple may introduce "plenty of spots for a new storage medium that Apple will introduce specifically for this machine."

It is possible that Apple will move to SSD or Flash drive options, which will save considerable space, although the user would have to pay more to get the same amount of storage.

Thunderbolt to trump PCIe in new Mac Pro

One way that the Mac Pro could be smaller is if Apple replaced the current PCIe expansion slots with Thunderbolt. Borella seems to consider this as feasible. He writes: "All of your expansion options will have to come via Thunderbolt," suggesting that Apple would refer to PCIe cards as "legacy". 

Borella goes on to suggest that the companies that have relied on PCIe expansion cards will have to switch to Thunderbolt connected devices. He adds: "I think Apple believes that a PCIe expansion chassis is a stopgap device until Thunderbolt specific hardware starts to show up."

A separate report from Peter Cohen over at iMore suggests that it's now possible to achieve broadcast-quality video input and output and use high-speed peripheral interfaces like Fibre Channel and eSATA with Thunderbolt adapters instead of a PCIe card. So the reasons for having a lot of expansion are decreasing.

"Let's hope they have found a way to keep the need for external devices to a minimum," Borella writes. One problem with favouring Thunderbolt over internal expansion options is it would mean more desktop clutter.

Thunderbolt adoption

Intel has come under fire recently for hindering adoption of Thunderbolt – a technology that it designed. A DigiTimes report criticised Intel's unwillingness to license the technology to other parties for a lag in adoption of the new standard, which was introduced two years ago.

However, Intel told Apple Insider that the DigiTimes report was inaccurate, noting that it is incorrect to paint Intel's as the "sole seller of technologies critical to Thunderbolt's operation".

"It's not proprietary or exclusive or anything. In fact, there are multiple suppliers that make the components," Intel's marketing director for Thunderbolt Jason Ziller told Apple Insider.

Graphics options in the new Mac Pro

Thunderbolt connectivity on the Mac Pro could also replace the need for PCI slots for GPU options. "As long at our future Mac Pro's GPU is beefy enough and equipped with enough VRAM, it's possible that it wouldn't even need slots for video cards," writes iMore's Peter Cohen.

However, Borella speculates that Apple might use the PCIe slots for "GPU options that will be offered at the time of purchase."

Borella describes the dual GPU capabilities referred to by his source as "welcome". He notes that Nvidia and AMD have released "many new GPU options on the Mac platform" over the past few months.

Apple is said to have hired around a dozen graphics engineers and graphics architects laid off by AMD earlier this year. The company is also said to be seeking a manager to lead the Orlando GPU team. 

The new Mac Pro CPU

While Borella's source doesn't mention the processor it is a fair bet that the new Mac Pro will sport a new Intel processor, and a new Xeon just happens to be scheduled for launch later this year.

Crucially this new Xeon will be able to accommodate Thunderbolt and USB 3.0, both of which are lacking from the current Mac Pro's Intel chipset and motherboard.

How about a MacMini Pro? 

Regarding the new design hinted at by his source, Borella admits: "Thoughts of a MacMini Pro do come to mind," adding that: "The earlier rumors of the 'modular' Mac Pro seem to be pretty close."

"I would think that this type of configuration would allow Apple to keep the initial cost of the machine lower with the expense coming in the external configuration options and GPU choices," he writes.

Will Apple reinvent the Mac Pro?

While Borella has his concerns about how Apple will arrive at this new, probably smaller design, he suggests that Apple may have come up with a solution that will surprise those who think that their existing workflows are the only solution to their problems.

He writes: "To truly see any benefit in this type of configuration you have to forget what you know about your existing machine. You are going to have to believe that Apple has thought about all the possible existing workflow's and has a solution that can replace them."

"When has Apple ever done anything that hasn't initially infuriated the Pro user?" Borella asks.

Follow Karen Haslam on Twitter / Follow MacworldUK on Twitter

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