Apple today announced a revised iMac based on the Intel “Sandy Bridge” chipset. This chipset is fantastic, and what is used in the fast 2011 MacBook Pro. The iMac offers (optionally) up to a 3.4 GHz processor which uses Turbo Boost to 3.8GHz — exceptionally fast.
Apple cripples the ability to replace a drive without the fans running loudly (but OWC offers a solution).
The fan issue is indicative of a design on the edge of reliability— heat stress over time. The previous model was hot enough to hurt my hands when touched, whether the 2011 model has the same issue I don’t know. But any computer running that hot is a very bad idea for longevity.
As I’ve made clear for years now, the iMac is a dead-end Mac in terms of value over time because of its serious upgrade limitations, some of them imposed needlessly by Apple. But it’s also about longevity; many Mac Pro users run their machines for well beyond the 3 years warranty possible with AppleCare. I seriously doubt that a well-used iMac would survive as long.
The top-end iMac should now easily match or outrun the existing 4-core Mac Pros, so that that makes the iMac viable in terms of pure CPU grunt. It should even rival the 6-core 3.33GHz Mac Pro for some tasks— see the 2011 MacBook Pro tests for a hint and note that the fastest MacBook Pro is running only at 2.3 GHz.
iMac memory up to 32GB
Since OWC offers up to 32GB of memory for the iMac, memory is no more an issue on the iMac than on the 4/6-core Mac Pros, though total memory bandwidth is somewhat lower (dual channel). And at present 32GB costs too much for 99.99% of users to contemplate for an iMac. But that price will come down.
By the way, save yourself a ton of money on memory— Apple wants a whopping $600 for 16GB, but OWC has it for about $208.
iMac I/O capabilities
At present, the dual Thunderbolt ports are good places to store used chewing gum. But when (relatively expensive) Thunderbolt peripherals appear, they will transform the iMac into a contender at long last, because fast disk I/O and/or RAID will become a reality. This has never before been possible on the iMac with its pathetic single Firewire 800 port.
Dual Thunderbolt ports
To work around the mirror-like screen (I have the Apple 27", I really dislike it), up to two 27" 30" displays can be connected, such as my favorite color calibrated displays: the NEC PA301W and/or the NEC PA271.
Setting aside the mirror-like display and the absence (yet) of any Thunderbolt peripherals (which won’t be cheap), the new iMac looks to be a viable alternative to a Mac Pro for the first time ever. That’s good news for those looking to start with an iMac, and move up in capabilities later.
Some realities still intrude: the iMac cannot accept PCIe cards, 32GB of memory at present remains very expensive, and video and similar users will still need 8 or 12 cores. If those limitations are acceptable, and you have faith in future Thunderbolt peripherals, the iMac might work for you.
New Mac Pro?
The new Sandy Bridge processor could be used in a Mac Pro as a single CPU. I think this would be a good path forward, especially if a new Mac Pro included dual or quad Thunderbolt ports. The question is whether Apple will wait longer for Xeon processors as have always traditionally been used in a Mac Pro.
Ideally, we’d see a mid-sized tower using the new Sandy Bridge chipset, along with 2 or 4 Thunderbolt ports, and at least two drive bays.