The Used Power Mac G4 Value Equation
My Turn is Low End Mac's column for reader-submitted articles. It's your turn to share your thoughts on all things Mac (or iPhone, iPod, etc.) and write for the Mac web. Email your submission to Dan Knight .
There has been lots of talk of how the Mac mini should depress prices for used G4 Macs (for example: Low End Mac's Best Used Power Mac G4 Deals and My Mac's After the Mac mini, is there still a market for used Macs?). Prices have fallen somewhat, but the value equation has not yet dropped to the point at which I would find a used G4 tower a competitive deal compared to a new Mac mini.
My university is offering surplus dual processor 533 MHz/40 GB/512 MB G4 machines for $499 with no monitor, no mouse, and no keyboard. I was tempted at first, but then did a comparison and changed my mind.
|Mac mini||Dual G4/533|
|G4 CPU speed||1.25 GHz||equal to 850 MHz|
|Bus speed||167 MHz||133 MHz|
|Memory||256 MB||512 MB|
|Display card||ATI Radeon 9200||Nvidia GeForce 2 MX|
|Video memory||32 MB||32 MB|
|Operating system||OS X 10.4||OS X 10.2|
Those are all relative concepts, so to put a price tag on the difference, a price differential was calculated by comparing the specs and then subtracting the same percentage of the price as there was percentage difference between the specs from the starting price of the Mac mini, because the used G4 was, for the sake of argument, worth that much less than the new Mac mini. The data are displayed in the table below, following the explanation of how the figures were arrived at.
The cost of adding additional memory to the Mac mini (BTO from Apple) was added to the price of the Mac mini make it equal the memory capacity of the G4. This started the price of the Mac mini at $550.
This Week's Best Used Power Mac G4 Deals says that "[a]s a very rough guide, a dual CPU model will outperform a single CPU model with a 60% higher MHz rating under OS X," which means that the dual processor G4/533 is roughly equivalent to an 850 MHz single-processor computer. That makes the Power Mac [850 MHz equivalent] approximately 32% slower than the Mac mini. That means that the G4 should be roughly one-third slower (and less productive) than the Mac mini.
The Power Mac's bus is 20% slower than the mini bus. That means that the G4 should be roughly 20% slower than the Mac mini. Since it is a dual CPU G4, however, for the sake of argument, the price differential will be considered to be only 10%.
The video cards (with 32 MB each) are considered equal for the sake of this comparison.
To approximate the value of the one-year warranty, the cost of 2 additional years of Apple care ($149) was divided by two, and the result was subtracted from the price of the G4.
No value was added or subtracted for the keyboard, mouse and display, as I have those already.
Starting Price for the Mac mini: $550
CPU speed: -$176.00
- Bus speed: -$55.00
- Display card: 0
- Tiger: -$99
- iLife: -$79
- Guarantee: -$74.50
- Total value: $66.50
The surprise total seemed to indicate that I should pay $66.50 to take the used dual processor G4/533 away, which is taking the argument to its illogical conclusion.
Editor's note: We realize that this article takes things to an illogical extreme. While CPU performance can be compared relatively easily, bus speed has far less impact on performance. Further, this article does not take into consideration the Power Mac's expansion slots, use of a 3.5" hard drive, multiple internal drive bays, and ability to use newer AGP video cards - none of which may matter to the potential Mac mini buyer.
A used Power Mac G4 does have some value. In deference to the "megahertz myth," the value equation was recalculated using just the value of Tiger, iLife and the "new vs. old" premium (i.e. the warranty) from the price of the used dual processor G4/533.
All other things being equal under this valuation scheme - which they are not - the used Power Mac is only worth $319. At that price, I might begin to be interested in one for a low-intensity workstation, which is the use for which the winner of this price comparison is destined.
Prices will not start to fall to this level, however, until those of us in the used Mac market begin to conceptualize this price differential and vote with our Mac-buying dollars that prices for used Macs are too high in comparison to the Mac mini.
It has reshaped the whole Mac marketplace, and its effects are just beginning to be felt.
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