There is a lot of FUD flowing between Apple Macintosh true believers and the rest of the PC world. This is especially true now that Macs use Intel CPUs, NVIDIA chipsets and graphics, and so much more commodity PC parts. Lots have argued that a Mac is just an expensive PC with a flashy case and slick operating system. Mac fans have to admit that there is a lot of commonality (Macs and PCs can even run each others’ operating systems with varying degrees of success), but contend that Apple uses superior components, justifying the “Apple tax”.
This last point has always been debatable as well. Apple tends to select higher-end x86 parts for their Macs and has led the way with innovative chassis, screen, and trackpad technology. But PC makers have quickly followed, offering part-for-part Apple clones at 80% of the cost. This week, however, I stumbled onto a concrete difference between Mac and PC hardware that has real-world impact: Across the board, Apple uses exclusive Intel CPUs with enhanced capabilities to support virtualization of 64-bit operating systems, including Windows 7’s special XP compatibility mode.
Virtualization hypervisors have become very widespread and popular, especially in the Apple world. Mac users regularly list Parallels Desktop and VMware Fusion among their favorite applications, since they open up the wide world of Windows applications running in a virtual machine. Although most daily tasks can be performed with native OS X applications, some apps just aren’t available.
Personally, I use Fusion on OS X with Windows Vista to occasionally run Microsoft’s Visio and Outlook, both of which aren’t available as native applications. I also use a 2009 Mac Mini as a server and virtual computer lab, mainly relying on Sun’s lightweight and free VirtualBox hypervisor. Although it isn’t impressive as the physical lab Dennis Martin described to me last week, I am able to run a variety of servers (Linux, Windows, and OS X) and other virtual gear (Windows Storage Server and FreeNAS) to simulate enterprise IT environments.
Windows users have less need to run virtualization applications: When your operating system commands over 90% of the market, a whole world of applications is at your fingertips! But enthusiasts and corporate IT types love virtualization, and VMware Server and Microsoft Hyper-V are commonly found on their Windows machines.
64-Bit Road Block
These popular virtualization packages support a wide range of modern hardware, but not everything works perfectly. Hypervisors had trouble with many tasks, particularly running 64-bit operating systems, until Intel and AMD introduced special hardware-assisted virtualization capabilities in their CPUs. The latest hypervisors and CPUs can now even virtualize 64-bit operating systems on top of 32-bit hosts!
But not all CPUs include this technology. Intel has a long history of artificially segmenting their product line by disabling certain features in low-end parts. For their Core 2 Duo “Merom” and “Penryn” lines, Intel decided that their VT virtualization technology would be the differentiator. Therefore, a lack of VT support is one of the main differences between low-end and high-end Intel Core 2 Duo CPUs.
Many of the latest portable and compact desktop systems use Intel’s Penryn-3M line, including Apple’s MacBook, MacBook Pro, and Mac Mini systems. See the issue here? Intel’s lower-end 2.0 GHz and 2.133 GHz CPUs (P7350 and P7450, respectively) don’t support VT, which means that systems using them don’t have the latest VT hardware virtualization capability and thus can’t run 64-bit virtual machines!
This is an issue for users of popular Sony Vaio, Dell Inspiron, and HP Pavilion PCs, and is likely to become much more important soon. See, Windows 7 includes a special XP compatibility mode, which is really just a virtual machine running XP under 7. But XP mode will not work without Intel VT or AMD-V. This means that XP mode in Windows 7 won’t work on the very mass-market machines that would benefit most from it!
This sounds terrible: The latest machines won’t run increasingly-popular virtualization software. But there is a very good reason that buyers of the latest Apple machines aren’t up in arms. It seems that Apple made a deal with Intel to get a special version of the Penryn-3M Core 2 Duo CPUs that do support Intel VT!
Apple’s latest Mac Mini, MacBook, and MacBook Pro all sport P7350 and P7450 CPUs, just like competing Dell, Sony, and HP machines. But the Apple CPUs have VT and the PCs lack it. The VT support is gone, and cannot be enabled in the PC BIOS.
So even a PC and Mac sporting the exact same CPU part numbers aren’t equal: Every recent Mac will run 64-bit Windows and XP mode in Windows 7 and many PCs won’t. And I can run anything I want on my Mac Mini virtual lab!
Update – Let me be very, very clear on the facts here:
- Most hypervisors now require Intel VT or AMD-V in order to virtualize 64-bit operating systems
- Microsoft requires this technology to use XP mode in Windows 7
- All current Apple Macs (including those that use P7350 and P7450 CPUs) have Intel VT support in their CPUs regardless of what Intel says on the model spec sheets
- Many PCs use high-end Intel and AMD CPUs that support VT or AMD-V, though some have this turned off in the BIOS
- No PC with an Intel P7350 or P7450 CPU has Intel VT support at all. It cannot be enabled in the BIOS because it does not exist.
I am not an Apple fanboy. I am a virtualization fanboy who is glad I bought a Mac Mini instead of a Dell Studio, HP TouchSmart, or Sony Vaio.