Thanks to Apple's build quality, old Macs rarely die – they just end up on eBay. You can get a usable machine from under £100.

To cope with modern life it'll need a G4 or higher processor and Mac OS X. Check the system requirements for any apps you want to run. Macs with PowerPC processors can't run Intel-based software, such as Windows under Boot Camp.

You can look up Mac specs at Apple's site; if a part number such as M8950LL/A is given, type it into the search box.

Wikipedia and LowEndMac.com are good for unofficial info such as known problems. Confirm with the seller that the OS X discs are included, as you'll need them in emergencies.

It's good if the OS has been upgraded to the highest compatible version – Mac OS X editions cost £25 to £75 on eBay – but do ensure the discs are supplied, and the same goes for any installed apps.

All non-prehistoric Macs have USB ports, but if they are USB 1.1 your iPhone, iPad or recent iPod may fail to connect: officially they require USB 2.

Check if Wi-Fi is installed: AirPort means 802.11b, and AirPort Extreme will be 802.11g; if not, search eBay for the appropriate AirPort card, or try a USB adaptor. Alternatively, all Macs have Ethernet ports to cable directly to your router or to an AirPort Express (£81), which then connects wirelessly.

Here's our pick of the sensible buys. Prices are for eBay; dealers will charge more but should offer some warranty and support.

iBook G4

Before the name was recycled, iBook was Apple's cheap laptop. The 1999 G3 clamshell model was wacky, but the white version (May 2001 to 2006) resembles today's MacBook. Of the 12-inch and 14-inch variants, the former is handier and has the same 1024x768 screen resolution.

Don't pay more than: £225, working down according to spec.

Will run: Mac OS X up to 10.4.11 Tiger.

Advantages: Affordable modern-feeling notebook – as long as you don't need demanding apps.

Disadvantages: Avoid G3; go for 256MB RAM or more; batteries can be replaced (Apple £89, eBay £20-ish).

eMac

Aimed vaguely at the education market, the eMac (2002-2006) was built around a CRT, like the original iMac, but with a 1280x960 17-inch display and a nicer white polycarbonate case. Even the internal speakers are good.

Don't pay more than: £75.

Will run: Mac OS X up to 10.5 Leopard (although 700/800MHz models officially go up to 10.4).

Advantages: With a G4 processor and proper graphics chips, performance is quite decent; April 2004 and later units have USB 2.

Disadvantages: CRT screens are good quality but dim over time and can't be replaced; many eMacs have no optical drive or only a CD drive.

Power Mac G4

Apple's plastic towers, with their flamboyant corner handles, are fantastic value now. It's as much about finding the best spec as the best price. Ignore the first-generation Graphite G4 and the Bondi Blue G3: you want the Quicksilver (2001- 2002) or Mirror Door (August 2002-2003).

Don't pay more than: £100 (Mirror Door), £50 (Quicksilver).

Will run: Mac OS X up to 10.5 Leopard; Mac OS 9.2.2 (not FireWire 800 models).

Advantages: Good performers for their age; easy internal access to components, plus space; fast Gigabit Ethernet.

Disadvantages: No USB 2 ports to connect recent mobile devices (but a USB 2 PCI card will fix that).

G4 Cube

We admit we've included this largely for sentimental reasons: units don't come up for sale very often and aren't necessarily a great buy, with limited performance and upgrade potential, and glitchy tendencies. But – well, just look at it!

Don't pay more than: £100, unless you're as sentimental as us.

Will run: Mac OS X up to 10.5 (Leopard), though officially only 10.4.

Advantages: Unless modified, the Cube has no fan and is almost totally silent; great conversation piece; uses desktop components, so some upgrades are possible.

Disadvantages: Cult status means sellers may overprice; compare Mac mini. Plastic can crackle – ask seller; most units CD only, none burn DVDs.

Power Mac G5

The predecessor of today's Mac Pro, this sleek aluminium tower (2003-2006) was the last Mac before the switch to Intel, coveted by aficionados of old-school software. Available with one processor (SP), two processors (DP), one dual-core processor (DC) or two dual-core processors (DP DC, aka Quad).

Don't pay more than: £150-£400 according to spec.

Will run: Mac OS X up to 10.5 (Leopard).

Advantages: Best performance from a pre-Intel Mac; at reasonable prices if you shop with care; can take 16GB RAM; USB2.

Disadvantages: Some single-core models had noise issues – check with the seller.

iMac G4

Known as the Anglepoise iMac (after the patented desk lamp), this unique model is said to have been inspired by Luxo Jr in the short film that launched Steve Jobs' film company, Pixar. LCD isn't as bright or sharp as today's displays, but it's still on a cool Mac.

Don't pay more than: £100 (15-inch), £150 (17-inch).

Will run: Mac OS X up to 10.5 (Leopard), though officially only 10.4.

Advantages: Striking and sturdy design with highly adjustable screen position; good Harman Kardon external speakers – check they're included.

Disadvantages: No way to add USB 2, though some users report iPhone will connect, with occasional glitches; RAM and hard disk can be small.

PowerBook G4

The G5 chip never took a portable form, so the G4 was the last Apple laptop before the switch to Intel. It resembles current MacBooks but has a more traditional keyboard. Numerous models were produced in 12, 15 and 17-inch formats, so studying the specs is essential to get the right deal.

Don't pay more than: £125-250 according to spec.

Will run: Mac OS X up to 10.5 (Leopard).

Advantages: Good-looking; 4-5 hour battery life (though original battery will tire if not already replaced); most units have USB 2 – check.

Disadvantages: Avoid titanium cased version; beware quality issues with certain batches.

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First published in MacFormat Issue 224

Liked this? Then check out 40 cool OS X tips to save you time and effort

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