Mac OS X performance
Beyond the basic system requirements for Mac OS X, we have found several factors that seem to influence how fast your Macintosh computer and applications respond. If you are interested in increasing the performance of Mac OS X through version 10.2 ("Jaguar"), we suggest improving the following factors (in no particular order).
Note: Overall system performance is a complex subject. We can provide guidelines based on our informal testing. None of these guidelines has been rigorously tested, and we provide them only as food for thought. Your experiences may vary.
- Upgrade the computer to 512 MB of memory or more. (Memory is measured in megabytes and gigabytes.) Performance seems to continue increasing with additional RAM. At 128 MB or 256 MB, your computer has enough memory to run Mac OS X and a few applications, but with more, Mac OS X can really start to shine. Most Mac OS X-compatible Macintosh models can support at least 384 MB of RAM, and some models can go as high as 2 GB. If you can (and if your Mac model can't support more 1 GB of RAM), max out the memory in your particular Macintosh model.
- Upgrade your video card. If you can get an AGP-based video card with 32 MB video RAM or more, that can allow you take to advantage of Quartz Extreme (first available in Mac OS X 10.2 Jaguar). This can make a significant difference in how fast the user interface of Mac OS X performs. Even if your computer does not have AGP slots, upgrading to at least an ATI Rage 128 with 16 MB of RAM will help speed up the computer, because even that will accelerate the Quartz graphics system in Mac OS X. Note that Apple iBooks, PowerBooks, iMacs, and eMacs cannot be upgraded to new video cards.
- Use a fast hard disk for your startup drive. Most current Macs use IDE/ATA-based hard disks by default, but lower-end computers from Apple have typically shipped with slower 5400 RPM drives. Replacing your ATA/IDE startup drive with one that spins at a rotational speed of 7200 RPM typically makes a difference on desktop Macs. We have not tested SCSI drives (either alone or against their ATA/IDE cousins), but some SCSI drives spin at 10,000 or 15,000 RPM and may be even faster, but could be overkill for a modern desktop computer. An upgrade from a 4200 RPM to 5400 RPM laptop drive can do similar wonders on a portable Mac. Other characteristics that can make one drive faster than another: low seek times (measured in milliseconds), high transfer rates (measure in megabytes per second), and larger in-disk caches (measured in megabytes). Also, while some people would recommend partitioning your hard drive (so that one physical hard disk looks like several different disks on your desktop), we do not currently recommend this.
- Get a PowerPC processor other than the G3. At equivalent clock speeds, we have found G4-based Macs to be noticeably more responsive in Mac OS X, which was not always the case in Mac OS 9. Newer Power Macintosh G5 models from Apple (which use the PowerPC 970 processor) should be even faster. More applications may be accelerated for the G4/G5 processors in Mac OS X, as well, because developers have had more time to optimize their programs for the special Velocity Engine features of the G4 and G5. Getting a G4 processor requires replacing your current processor or replacing the entire computer, depending on your Macintosh model. As of this writing, there are no upgrades to G5-class processors for older Macs.
- Use a faster processor. The processor is the brain of the computer, so getting one with a higher clock speed (measured in megahertz or even gigahertz, which is one thousand megahertz) can allow it to handle more instructions in the same amount of time. Upgrading to a faster processor requires replacing your processor or buying a different Macintosh model. Another telling feature of higher-end G4 systems is the amount of Level 3 (or L3) cache memory dedicated to each processor. From our experiences, models with some L3 cache on a G4 are faster than those having none -- a good figure is probably 1 MB per processor. The G5-class systems do not use L3 cache at this time, and may not benefit from it.
- Use two processors. Apple sells Macintosh computers with two processors, and Mac OS X can benefit greatly from this. If you've taken care of the other factors above, having a second processor will provide extra computing power. Again, twin processors may be available as an aftermarket upgrade for your computer -- or more likely, it may require the purchase of an entirely different Macintosh.
Whenever you consider an upgrade, you should think about:
- The cost of the upgrade compared to its benefits. (We cannot provide absolute measurements of the benefits.)
- The cost of all of the upgrades you think you need compared to the price of a new computer with better initial specifications.
If you are purchasing a new Macintosh computer, you will want to look at the features above to determine whether the computer meets or exceeds them. Try to get all or most of these performance features in a computer that meets your budget.
Again, the guidelines above are suggestions about what to look for in upgrades or a new computer. They have not been tested in a controlled setting. Please keep that in mind in your decision-making process. Your experiences may vary.