Intel will be continuing to segment power dissipation into two categories, which it introduced with the line of fast Northwood processors in Socket 478. This categorization, called FMB for "flexible motherboard", became relevant upon the rollout of the Prescott. Mobo manufacturers were able to design low-cost boards in line with Prescott FMB1 that tolerated a maximum 89 W of processor power dissipation. High-end models had to meet FMB1.5, which permitted using the fastest processors putting out up to 103 W.

In socket 775 architecture, there is now a distinction made between "mainstream" and "performance" FMB. Mainstream designs guarantee a maximum of 84 W, needed for Pentium 4 processors up to the 550/3.4 GHz model. Mainboards meeting the performance FMB specification, however, have to be able to handle up to 115 W of dissipation from the CPU.

Whereas the Pentium 4 600 can still be operated within the so-called "thermal envelope" at 115 W, this no longer holds for the Prescott successor Cedar Mill (coming in 2006) and dual-core processors, starting with the Smithfield. It is likely that Intel will introduce the FMB standards for 2005 upon rollout of the next chipset generation, code-named Glenwood for the 955 and Smithfield for the 945 family. These provide for up to 95 W for mainstream FMB, and a hefty 130 W thermal design power for performance FMB. We can only hope that all future processors will feature clock-speed and energy saving mechanisms like SpeedStep.

Selection Criteria

There are two major criteria that users typically consider in selecting mainboards. One is performance, including the features and functions offered. The other is the reputation of the manufacturer, which they assess either from good prior experiences or a lack of negative experiences. Users already happy with a particular manufacturer will normally start first by looking at other products from that company. This means that larger outfits like Asus, MSI, and Gigabyte, which have boards sold nearly everywhere, have an advantage in the area of repeat buying by loyal customers.

For this reason, we deliberately chose manufacturers with a smaller market presence for the first part of our test. These companies' products always feature details designed to differentiate them from the pack.