Motherboards

In an ideal world, everybody would be able to buy a Core 2 Extreme CPU and upgrade it every few months when Intel released a newer model. In the real world, this isn't possible. However, it's possible to buy a lower-spec Core 2 CPU and overclock it so that it delivers a level of performance similar to that of a Core 2 Extreme, but for a fraction of the price. This requires a good CPU cooler, quality RAM and a stable PSU; most importantly, though, you need a good-quality motherboard.

The quality of the motherboard you buy will determine how far you can overclock your CPU more than any other factor. A crap motherboard will mean the CPU bombs out after 200MHz or so, while a good board will be able to boost your CPU by a gigahertz or more. So for this Labs test, we rounded up 13 new motherboards and exhaustively tested them to find out which is the best for you and your CPU.

Each motherboard in this Labs test offers some form of future proofing. They all claim to support the forthcoming 45nm Penryn architecture Core 2 CPUs, and some even offer support for PCI-E 2.0 graphics cards and DDR3 memory.

This Labs test isn't just a selection of expensive motherboards though; you'll also find great models from as a little as £49. Read on to find out which motherboard should accompany your choice of Core 2 CPU.

Motherboards are extremely complicated PC components to test, as there are so many different elements that comprise a good board. Factors such as the layout of the traces and the positioning of every component, from the Northbridge to each lowly resistor and capacitor, all have an effect on how well a motherboard performs. Throw in the dark art of BIOS programming and how well each component is cooled, and it's no wonder that some motherboards struggle to overclock while others deliver amazing performance. This is why we take motherboard design so seriously at Custom PC. A well-designed motherboard will allow you to overclock your CPU well beyond its stock frequency.

Before benchmarking each board, we update the BIOS to the latest public release, and use the latest core logic chipset and graphics card drivers. We then benchmark each motherboard at its BIOS defaults using the 2007 version of our Media Benchmarks and the Supreme Commander game test at 1,280 x 1,024 with 2x AA. This tells us how fast each motherboard performs at its out-of-the-box settings. Once these tests are complete, we attempt to overclock each motherboard to find the maximum FSB at which it can complete our benchmarks without crashing.

As most Intel CPUs have a locked clock multiplier, we overclock Core 2 motherboards by raising the FSB of our Core 2 Duo E6750 CPU until the motherboard won't benchmark stably. This typically requires boosting the vcore to 1.525V so that our test CPU can run at its maximum stable frequency of 3.66GHz. Our Core 2 test rig comprises a 2.66GHz Core 2 Duo E6750, 2GB of Corsair XMS2-8500, a 250GB Samsung SpinPoint P120S hard disk and a 320MB BFG GeForce 8800 GTS graphics card. Once that test is complete, we then try to decrease the clock multiplier of the CPU in the BIOS from eight to six, so that the motherboard, rather than the CPU, is the bottleneck when overclocking. Typically, this allows us to overclock each motherboard much further than when the clock multiplier is set to eight. The result of this test suggests how well the motherboard will be able to overclock CPUs with a multiplier lower than that of our test chip, as well as providing an indication of how far you can push a high-end CPU using exotic cooling hardware, such as a water-cooling kit or phase-change cooler.

We also assessed the features of each motherboard, such as the number of S-ATA II ports, the quality of the on-board sound and the component layout. For example, motherboards with widely spaced PCI-E slots are awarded more features points, as it will be easier to cool graphics cards on these motherboards. We also paid close attention to the CrossFire and SLI motherboards to ensure that you can still use the PCI slots even with two dual-slot graphics cards fitted. We then calculated the overall score for each motherboard by a weighted average of the performance (stock and overclocked), maximum stable FSB, features and value for money.