Motherboards Group Test

Darien Graham-Smith | 1 Sep 2008

With so many factors to consider, choosing a motherboard can be a bewildering exercise. We put 11 models through their pace to find the ultimate in performance, flexibility and value

When we talk about a computer’s specifications, we tend to focus on its components – the CPU, graphics card, RAM and hard disks. But if you’re building a PC, there’s another fundamental component you can’t neglect: the motherboard.

To an extent, your choice of mother-board is determined by the components.
If you plan to use an AMD CPU, you need a board with an appropriate socket. To use one of Intel’s 45nm chips, you’ll need a chipset that supports it.

Expansion potential is also key: different boards offer different combinations of PCI and PCI Express slots, and different numbers of SATA and USB connectors. Some add eSATA, FireWire and dual ethernet ports; others sacrifice features to lower the price.

Graphics support is another consideration. Some boards have onboard graphics, but most need a separate card. Some chipsets will drive multiple ATi graphics cards, while others can only do that with Nvidia cards.

Finally, it’s worth giving a thought to the BIOS. Some boards make it easy to tweak your system, while others are more restrictive.

This month, we compare a wide range of motherboards and weigh each one’s potential, taking into account all these issues – plus the all-important question of value. We also look at the merits of different chipsets and consider power consumption, too. If you’re thinking of building a system, read on to find the right board at the right price.

How we test

This month, we put 11 motherboards to the test. It’s a complex task, as every one of these boards offers a unique combination of features. Measurements and benchmarks can therefore tell only part of the story: choosing a motherboard is often less about performance than capability.

But that’s not to say there’s no room for empirical analysis. Over the following pages, you’ll find a detailed discussion of each board’s various strengths and weaknesses, coupled with scores allocated to each based on a combination of subjective judgments and objective measurements. And, as usual, at the bottom of each review you’ll find marks in four categories: Performance, Features & Design, Value for Money and a final Overall score.

Performance
Each board’s Performance score is calculated from three factors. The first is a measurement of actual system performance. You might imagine that this is wholly down to the CPU, RAM, chipset and graphics card, but it’s the motherboard chipset that handles communications between all of these components (see page 66). And the various boards in this month’s test use a total of nine chipsets from three different manufacturers, so it’s to be expected that some boards will manage to squeeze a little more performance out of a system than others.

To measure the real-world performance gap, we build a standard system based on each motherboard; depending on the board’s requirements, we install either an Intel Core 2 Duo E8500 or an AMD Athlon 6400+, with 2GB of either DDR2 or DDR3 RAM. We then run our standard benchmarks (see the “Real World Benchmarks” PDF in the Editorial section of our cover disc) and record the difference in scores achieved.

The results are expressed in the graph above as a proportion of the average score for that CPU. As you can see, we observed a small but real variation of around 2% between boards. Since the difference is so small, it has only a minor effect on each board’s Performance score. However, it’s interesting to note that the slowest and fastest boards are both DDR3-based, indicating that, while the newer standard can achieve higher speeds than DDR2, simply using DDR3 won’t magically improve performance.

Click to Enlarge: Motherboard Performance and Power Consumption

The Performance score is also affected by power consumption. To measure this, we use each board as the basis of a minimal system, using a 65W TDP processor (either a Core 2 Duo E6700 processor or an AMD Athlon 64 X2 4200+), two 1GB DIMMs and a passively cooled Nvidia 8500 GT graphics card.

We don’t take our readings while running Windows, for the simple reason that Windows’ many background services can cause a seemingly idle computer’s power draw to fluctuate by more than 5W – enough to obscure the differences between several boards. So, instead, we take our reading from the main BIOS screen, after waiting five minutes to ensure the components are completely stable and idle.

The results are shown above, but when reading the graph remember that some of this month’s boards feature integrated graphics, meaning they can run without a graphics card. Real-world power consumption could thus be around 30W lower than the figure quoted above, although, of course, you won’t be able to get the best out of modern games.

Finally, the Performance score also takes into account how far the BIOS lets you tune your PC’s performance. Top marks go to boards that make it easy to monitor and tweak settings such as the RAM frequency and the CPU multiplier. Lower marks go to less user-friendly or fully featured BIOS implementations.

Our scores are based on the current BIOS version as we went to press, but all manufacturers offer downloadable updates. So, if a board you like is missing a particular feature, check the website in case it’s since been added.

Features & Design
Our score for Features & Design is self-explanatory. As you’ll see from the table opposite, no two boards offer quite the same range of features and expansion options. Our rating represents how well featured each board is, taking into account issues such as the number of USB connectors, PCI slots and SATA channels, and whether the board has multi-GPU support. We also consider any thoughtful design aspects – clear labelling, internal power switches and so on. These aren’t so heavily weighted, though, as once your system is up and running you may never need them again.

Value for Money
The Value for Money score reflects each board’s price, but top marks don’t just go to the cheapest contender. We take each board’s score for Performance and Features into account, so a high score here means a board is particularly good for its price.

Overall
Finally, our overall score is an average of the other three, although it may be higher or lower than expected due to rounding.

Hybrid Graphics
If you’re looking for a motherboard with an integrated GPU, one phrase you’re likely to encounter is ‘hybrid graphics’. Until recently, you had to make a straight choice between using the integrated graphics processor (IGP) or a discrete graphics card. Within the past six months, though, both AMD and Nvidia have started shipping chipsets that can combine the strengths of both GPUs – hence, hybrid graphics.

There are two distinct ways to take advantage of hybrid graphics. The first is a system Nvidia calls HybridPower. The idea is simple: when you’re working in Windows, or doing some other task that doesn’t need the full grunt of a separate graphics card, the card is powered down and the low-power onboard graphics chip is used instead. When you launch a game, the card is dynamically woken up to take over 3D graphics processing. Whichever GPU is doing the work, the chipset routes the signal to the right socket, so you don’t need to switch cables around.

Since a high-end graphics card can draw more than 100W even when idle, this system can save a lot of power without any cost in performance. AMD has a similar system, which it calls PowerXpress, but for now it’s only available on laptop chipsets.

The second aspect of hybrid graphics is a system called either Hybrid CrossFire or GeForce Boost, depending on which camp you’re in. This lets you combine the 3D processing power of the onboard GPU and a compatible discrete card in the same way as standard CrossFire/SLI.

We tried this system out with the Hybrid CrossFire-equipped Gigabyte GA-MA78GM-S2H. Running our Crysis benchmarks with the integrated Radeon HD 3200 GPU, we achieved an average frame rate of 17fps at 1024 x 768 with low detail. Turning detail up to medium slashed that to 8fps. With a discrete Radeon HD 3450, frame rates rose to 25 and 11fps respectively. Enabling Hybrid CrossFire nudged scores up just a tiny bit further to 27 and 12fps. We’ve seen before that 3D games simply don’t scale well across multiple GPUs, and it seems that’s especially true when one of the GPUs is a lightweight IGP.

The theory behind hybrid graphics is a good one, and Hybrid Power is a great way to save energy. But, based on our Crysis tests, we’d have to say Hybrid CrossFire is an idea ahead of its time, and not one we’d recommend basing a purchasing decision on.

Chipsets: A bridge too far?
This month, we’ve focused on each motherboard’s capabilities and features. But to an extent these are a function of the chipset on which the board is based.
The chipset consists of two separate controllers, known as a north bridge and a south bridge. The north bridge handles communications between the high-bandwidth parts of a PC; typically, the processor, system RAM and graphics card slot.
It also connects directly with the south bridge, which handles less demanding components, such as USB ports, SATA controllers, ethernet and any old-style PCI slots. Some south bridges include integrated graphics, too.

The efficiency of the chipset can affect the performance of the entire system (as you can see in the graph on page 56), and its capabilities dictate which components the motherboard can support. For example, an older chipset may be unable to run a brand-new processor at full speed. And you won’t be able to use multiple graphics cards unless your north bridge is specifically designed to handle that.

There are three major chipset manufacturers: AMD, Intel and Nvidia. Not surprisingly, AMD’s current offerings are all designed to work with AMD’s own processors. You’ll still see boards based on the old 690 chipset, but the current range is the 7 series, which comprises the 740, 770, 780 and 790, plus a few variants, which are indicated by a suffixed letter.

At the bottom of the range, the 740 supports just a single PCI-E 16x slot, and a maximum HyperTransport frequency of 800MHz. The top-end 790FX, meanwhile, can handle four ATi graphics cards at once (two at PCI-E 16x speed, two at 8x) and supports HyperTransport speeds up to 2.6GHz.

Intel’s chipsets likewise support only Intel processors. Intel offers a wider range of chipsets than AMD, but on a modern motherboard you’re most likely to see the P35, X38 and X48. The P35 is a good all-rounder, supporting all recent Intel processors with its 1333MHz front side bus and accepting both DDR2 and DDR3 memory, although motherboard manufacturers generally implement only one or the other. It’s limited to just one PCI-E 16x slot, though: if you want a second slot, you’ll need to move up to the X38 chipset, which also adds support for ATi’s CrossFire X system (despite the fact that ATi is now owned by Intel’s competitor, AMD).

Finally, the X48 lets you overclock both the RAM and front side bus up to 1.6GHz and promises future support for 10 Gigabit ethernet, although that has yet to appear on the market.

The third major player, Nvidia, makes chipsets for both AMD and Intel processors. The current range for AMD CPUs is pretty small, though, extending only to the nForce 720a and nForce 730a, and the only difference between the two is that the 730a has a more powerful integrated graphics chip. More powerful chipsets are expected soon that will add three-way SLI and faster memory support.

On the Intel side, Nvidia’s older 600 series motherboards are still popular – there are two in this month’s Labs – while the current range consists of the 750i, 780i, 790i and 790i Ultra. Features improve as you go up the range, maxing out with the 790i Ultra – as seen this month in the Asus Striker II Extreme – which will drive up to four GPUs at once.

For most purposes, you can get by without worrying too much about which chipset a motherboard uses: after all, it’s the features that are important rather than the chips themselves. However, as we’ve seen, the chipset does have a small effect on system performance. And if you have an eye on future upgrade possibilities, a newer chipset is more likely to work with as-yet unreleased hardware than will one that’s already approaching the end of its life.