Product Reviews

At current prices, Intel's 2GHz Pentium 4 processor costs the same as two of AMD's 1.53GHz Athlon XP 1800+, with change left over. In some situations, just one Athlon can outperform the Pentium 4 anyway. So, if you're in the market for upgrading, or even building from scratch, you can now consider dual processing without breaking the bank. We put this to the test using two new boards from Asus: one using the Intel 845D DDR Pentium 4 chipset and one using AMD's latest 762 dual Athlon MP chipset.

Asus' P4B266 Pentium 4 motherboard costs £143 and features integrated C-Media six-channel audio as well as USB 2. A worthy software bundle includes C-Media audio applications, Live Update for easily updating the BIOS from within Windows, and PC Probe to monitor the temperature and voltage of the memory and CPU as well as fan speeds.

PC Probe can be put to good use, particularly if you want to overclock. As a further aid, the AwardBIOS allows for an adjustable CPU/memory frequency ratio of either 1:1 or 3:4, fine-tuning of the system bus up to 200MHz in 1MHz increments, CPU frequency selection up to a 24-speed multiplier and five core voltage settings.

In terms of layout, the P4B266 is unimpressive. The memory slots are too close to the AGP slot, meaning long AGP cards will have to be removed when inserting memory, while the close proximity of the IDE and power connectors causes unnecessary cable clutter. However, one highlight of this board design is Asus' use of a standard 12V power connector to supplement the power required for the Pentium 4, meaning that you won't need to invest in a new power supply.

On the AMD front, the £193 A7M266-D is only marginally cheaper than Tyan's Tiger MP S2460 (see Labs, issue 89, p98), with the main difference being that the Tiger features four 32/64-bit 33/66MHz and two 32-bit 33MHz PCI slots, whereas the A7M266-D features two and three respectively. Integrated audio is the same as the P4266B and although no S/PDIF backplate

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is supplied, C-Media's six-channel output can be accessed through the main I/O backplate. Extra backplates are supplied to provide two extra USB 1.1 ports and a MIDI/joystick port. As with the P4B266, using both extra backplates prevents use of two PCI slots. The software bundle supplied is, not surprisingly, similar to that found in the P4B266 box.

Overclocking facilities are minimal on the A7M266-D, though, with the FSB adjustable from 100-133MHz in six steps via dip switches and jumper settings for 16 core and three DDR voltages. The AwardBIOS will only allow for switching between two CPU frequencies too.

The board design of the A7M266-D is much cleaner and there's ample space for the huge Athlon heatsinks. The CPU fan connectors are conveniently located, and there are an extra two labelled chassis and power supply. The main layout concern is the positioning of the IDE channel connectors, which are pushed much further down the board because of the space taken by the processors. This means cables from drives in the top bay will struggle to reach. Unlike the P4B266 board, two extra power connectors are required, which will most likely mean a power supply upgrade.

For performance testing, we used the same AMD and Pentium 4 rigs as in the motherboard Labs (issue 89, p80 and issue 88, p96). Additionally, two Athlon MP 1900+ processors were used to compare directly with the aforementioned Tyan Tiger MP S2460. Using a 1.5GHz Pentium 4 and 64Mb GeForce3 Ti 500, the P4B266 achieved 3DMark2000 and 2001 scores of 7,319 and 6,416 respectively, and a 2D benchmark score of 3.29, ranking in the bottom half of the 18 boards seen in issue 88.

Using the same graphics card, the dual Athlon board returned a 2D benchmark score of 4.59 with only one Athlon MP 1900+ processor installed. With both MPs installed, this score increased marginally to 4.61. However, the performance increase is more significant when using true multithreaded applications such as our LightWave benchmark. The rendering time of our test scene speeds up from nine minutes, 44 seconds with one Athlon to eight minutes, 21 seconds when two Athlons are used. This is a marginal improvement over the Tyan.

There's no doubting the dual-processing route provides performance dividends, and Asus offers an excellent platform. That said, there's the extra cost and inconvenience of replacing your power supply. As for the P4B266, the features are tempting, but the relatively poor performance can't be ignored. The Pentium 4 motherboard Labs Winner, MSI's 645 Ultra, is still a better choice.