Like many Apple customers who bought a Power Mac G5, dual processor, back in 2003 or 2004, mine is finally reaching the end of its lifetime. In my study of the new Mac Pro, I've discovered some interesting things that I want to share.

First, my Power Mac G5 (PMG5), bought in November 2003, has been a real workhorse. That's not to say there haven't been hiccups. I bought it with AppleCare, and at the 2.7 year point in the three 3 year coverage, I had a complete failure of the motherboard and one CPU. My local Apple store replaced the motherboard and both CPUs, invoice cost: ~ US$2,000. Cost to me: zero. It's been working fine, mostly, ever since.

Original Power Mac G5

However, little things are starting to go wrong now. One USB port is problematic. The trusty old Mac often has nightmares, forgets to talk to the fans while sleeping, and goes into wind tunnel panic mode. Good thing it can't sleepwalk. The original 160 GB hard disk, almost six years old, can't be trusted for much longer. FireWire 400 drives never did work well on the bus with the original iSight camera, an Apple bug, but I never pursued the issue. So it's time to upgrade.

I had toyed with the idea of an iMac, but my biggest complaint there is that a desktop Mac should have a lot more computing power than a notebook. I have been hoping that Apple would introduce a quad core iMac, but it hasn't happened, and now it's show time for me.

The Nehalem Series of CPUs

As I studied the new Mac Pros, I noticed that the Nehalem processor code name is very broad. The Wikipedia article on Nehalem shows the family tree and reveals that the eight core Mac Pro is based on the "Gainestown" 5500 series as follows:

2.26 GHz:  E5520
2.66 GHz:  X5550
2.93 GHz:  X5570

The Gainestown is classified as a server with dual processors (DP), each with four cores, and these Gainestown CPUs are expensive.

The quad core Mac Pro uses the "Bloomfield" line as follows:

2.66 GHz:  W3520
2.93 GHz:  W3540

This uniprocessor (UP) system, with four cores, uses chips that are a lot less expensive.

Mac Pro, Early 2009 (courtesy: Apple)

Memory Configurations

For technical reasons as well as cost reasons, I'm guessing that Apple elected to only put four memory slots in the lower end quad core Mac Pro. With 2 GB DIMMs, one can put a maximum of 8 GB in that system, according to Apple. For unknown reasons, Apple is currently deprecating the 4 GB DIMMs which are, incidentally, a lot more expensive.

My colleague, Ted Lanudau, reports that Other World Computing (OWC), a major reseller of memory, has tried putting 4 GB DIMMs in a quad core Mac Pro, and all is well. That raises the maximum memory to 16 GB, sufficient breathing room for growth if I also keep this Mac for 5+ years like the PMG5.

On the other hand, the eight core high end system has 8 memory slots, and 4 GB DIMMs are not deprecated. So one can put 32 GB of RAM in that system out of the box. I'm monitoring closely this mystery regarding the quad core Mac Pro memory.

Display Issues

When I drag iTunes protected video off the display of my MacBook Pro, with a DisplayPort to DVI connector, to the cinema display, I get a nastygram. The protected content can't be displayed there. This is part of Apple's sequential move to add DisplayPort for all its Macs to accommodate Hollywood's demands that protected (HD) content be encrypted between the source and destination.

Ted Landau reports that he dragged an HD TV show from his DisplayPort Cinema Display to an external DVI-based Samsung, and the content continued to play. So this is a topic of interest to me. One could save a little money with a nice but inexpensive Samsung 24-inch display for a fraction of the cost of Apple's (awesome) 24-inch LED backlit Cinema display. Time will tell.

I Feel the Need for Speed

My personal rule for upgrading to a new desktop is that the new Mac has to have four times the computational power. I've been monitoring the benchmarks over the years, and the original (indeed even recent) Xeon-based Mac Pros didn't meet that standard for me. Now, however, with the new Mac Pros using an integrated memory controller and bypassing the legacy front side bus (FSB) contention issues of yore, I think that a 2.66 GHz quad core Mac Pro fully meets the standard of four times faster than my dual processor, 2.0 GHz, PowerMac with its IBM PPC 970 CPUs. The original PMG5 sold for $1,999, so the new quad core Mac Pro is roughly in the same price class.

In fact, when Snow Leopard ships, with the aid of Grand Central (better, easier CPU threads) and OpenCL (using the graphics processor as an extra core) there's no doubt now that the quad core Mac Pro and Snow Leopard are on my hot list for the summer of 2009.

When Apple announces new computers, there's a lot of marketing glitz and emphasis on new technologies -- on a surface level. However, it's not a bad idea to wait just a bit, let the Internet bubble up with deeper info and dig into the details. There are always tradeoffs, like the ones I've described above, to be aware of.