Before you rush out and start spending, it's well worth weighing up the pros and cons of upgrading versus buying a new Mac.
This will depend on what you really want to get out of your upgrade. If you have a G4 tower, for example, and are really struggling to run the software you want, buying and fitting a new CPU, more RAM and larger hard drives might work out more expensive or comparable to buying a new iMac or Mac mini.
If you don't need the PCI slots of a tower, by buying new you will get a new warranty and a very slick piece of kit. The Intel processors in all new Macs also trounce even the fastest G4 upgrade card you could buy, if we're being honest.
Compared to a decade ago, Macs are now a lot cheaper and their performance far better than anyone could have guessed at that time. Consumer models like the MacBook and Mac mini, aggressively priced to lure switchers away from PCs, sell incredibly well and have specs not so far removed from the Pro portables and iMac.
The Mac Pro, though not exactly cheap, is an absolute powerhouse with eight processor cores as standard and the ability to hold a colossal amount of RAM and internal storage. Another factor to bear in mind is that as time goes on, Apple will eventually phase out support for PowerPC processors from its newest operating systems.
Some believe this could even be the case with Mac OS X 10.6, which will be optimised for Intel CPUs. It's not yet clear if G4s and G5s will be supported but even if they are, you're far better future proofed with a Core 2 Duo Mac than a PowerPC one, not to mention the fact that 10.5 will run more comfortably on faster chips.
Of course, if you're quite happy with 10.4 or 10.5 and feel no need to have the very latest system, most G4s – and certainly G5s – will run them perfectly well provided you have a healthy amount of RAM installed.
The upgrade path
There are also, of course, compelling reasons to upgrade rather than buy new. Many people are attached to their older Macs not just because they were an investment but also because, unlike PCs, Macs have a bit of character about them, so it's not quite as easy to treat them as mere commodities.
In cases where someone has invested a lot of money in a setup – for music, video or printing, for example – it can be that newer Macs or operating systems are incompatible with their expensive peripherals.
Imagine you have PCI cards hooked up to top-end printers or audio interfaces, but they only work on a G4's PCI bus and not those of newer Macs; you would want to keep the G4 for compatibility, but need to upgrade its components to get maximum performance. Or let's say the software you invested in several years back won't run on 10.5 but it does on 10.3, a system unsupported by newer Macs; keep the old machine but give it a speed bump.
The crucial thing to consider when upgrading is what specifically you want to improve about your Mac. Adding bigger, faster hard drives is relatively cheap and will give you lots more space for storage, and adding RAM is similarly fairly inexpensive and a good way to make your Mac snappier and more responsive. But neither of these would help all that much if, for example, you wanted to play the latest games. For that, you would need a faster graphics card.
Or let's say you wanted to run the newest music or video software. In this case, faster processors would be the key. None of these upgrades is going to do anything negative – adding RAM is always a good idea – but tailor your upgrade choices to the tasks you want to achieve.
Running an old Mac as a music server, for example, you can get away with a slower processor but it would benefit from bigger drives and a wireless or Ethernet card to hook it into your network.
Upgrading the processor is the most fundamental change you can make to a computer, and there's still a surprisingly robust selection of upgrade cards available for G3- and G4-based Macs and even earlier models.
The upgrade phenomenon skipped G5s, but if you're a confident techie or can get someone to fit it for you, an upgrade card can breathe new life into a G3 or G4. There are several advantages to upgrading the processor in an older Mac. You can generally get a dual processor upgrade card, which combined with the faster clock speed will bring a big speed bump over a single processor machine, especially given the multi-processing abilities of recent versions of Mac OS X.
A faster CPU will often mean you are able to install a later version of OS X on a machine previously unable to pass the installation requirements. The only thing to watch is compatibility between a card and the specific version of OS X you want to install, as occasionally there can be issues.
Finally, there is a simple way to upgrade any Mac – just add external peripherals. The most obvious example is a FireWire or USB 2.0 hard drive, onto which you can dump iTunes or iPhoto libraries, iMovie projects and more, greatly increasing the space available to you.
If your Mac can't house an AirPort card due to its age, try a USB WiFi dongle to get it onto your network. If your wireless network reception is poor, try a booster antenna to improve it. Plug in a Mighty Mouse or another mouse with a scroll wheel and programmable buttons and you'll have better control over your Mac.
If you don't have an iSight camera built in, you may be able to use a digital camera or third-party webcam instead with enabling software such as Macam (on the disc). Even the most technophobic Mac user can upgrade certain things without having to get their hands dirty!
First published in MacFormat, Issue 203
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