Arbico Phenom 5550 QCS review

When a quad-core processor is tested in the factory, sometimes one or more of the cores fail the manufacturer's quality control, and so these cores are disabled and the processor is sold as a dual- or (in AMD's case) a triple-core processor. The Phenom II X2 550 is actually a quad-core processor with two cores disabled, but Arbico has unlocked these disabled cores. The company has guaranteed that it has an adequate supply of stable, unlocked 550s to fulfil orders for the Phenom 5550 QCS.

The result of this unlocking is a noticeable performance jump. When we tested the Phenom II X2 550 Black Edition recently, it scored 91 overall, whereas Arbico's Phenom 5550 QCS scored 108 and posted consistently higher scores in the other tests, too. This means it's powerful enough to handle just about anything you'd care to throw at it.

Along with the fast processor, Arbico has installed a Radeon HD 5550 graphics card. This wasn't powerful enough to run Call of Duty 4 at a playable 30fps, but if you reduce settings, for example by turning off anti-aliasing, you should see smooth gameplay. It's capable of playing older games, but as more and more games use the latest 3D technologies to increase realism, you'll find the 5550 will hold you back. It will also speed up applications, such as the latest version of Photoshop, which support GPU acceleration.

Inside the Phenom 5550 QCS you'll find plenty of room for expansion, with free drive bays and SATA ports for extra storage. There are three PCI and two PCI-E x1 slots for TV tuners and other cards, although one of the PCI-E x1 slots is rather too close to the graphics card's fan for comfort. With two free RAM slots, upgrading your memory won't mean throwing away the existing pair of memory sticks.

A total of eight USB2 ports is reasonable, but two of these are taken up by the budget Logitech keyboard and mouse set. The keyboard has quite a light action but feels spongy, which reduces feedback, and the mouse has only two buttons and is very light. There aren't any eSATA ports, and no support for the latest USB3 standard, but there's one FireWire port mounted on the front panel.

Sadly, Arbico has compromised on the monitor and opted for a budget 19in Digimate. We've come to expect a 22in monitor as standard, even at this low budget, and despite decent image quality, the Digimate's 1,440x900 resolution and small dimensions feel cramped when compared to the Full HD 1,920x1,080 resolution that you'll find on most 22in monitors.

Without the monitor, the Phenom 5550 QCS still costs £460, mainly due to the expense of the graphics card which won't satisfy serious gamers. If gaming isn't a requirement, CyberPower's Infinity i3 Apollo XT base unit is better value at £418 thanks to the faster CPU.