Intel 925X Roundup: Creative Engineering 101

Abit AA8: Features and Layout

Abit AA8 Motherboard Specifications
CPU Interface	Socket 775 Pentium 4 (Prescott)
Chipset	Intel 925X/ICH6R
Bus Speeds	200MHz to 336MHz (in 1MHz increments)
DDR2 Speeds	Auto, 400, 533
PCI Speeds	33.33, 36.36, 40.00
Core Voltage	1.4375V to 1.7875V in 0.0125V increments
DRAM Voltage	1.80V to 2.25V in 0.05V increments
NB (Northbridge) Voltage	1.50V-2.05V in 0.05V increments
Memory Slots	Four 240-pin DDR2 533 Slots Dual-Channel Unbuffered Memory to 4GB
Expansion Slots	1 PCIe x16 Slot 3 PCIe x1 slot 2 PCI Slots
Onboard SATA/IDE RAID	4 SATA 150 drives by ICH6R Can be combined in RAID 0, 1, Intel Matrix
Onboard IDE	One Standard ATA100/66 (2 drives)
Onboard USB 2.0/IEEE-1394	8 USB 2.0 ports 3 IEEE 1394 FireWire Ports by TI 4200R7T
Onboard LAN	Gigabit Ethernet by Realtek 8110S-32
Onboard Audio	Realtek ALC880 (HD Audio) 8-Channel with SPDIF in/out
Tested BIOS	1.3

The AA8 DuraMAX is Abit's flagship board for the Pentium 4 LGA 775. This is reflected in the feature set, but the AA8 was also designed to sell at a rational price point compared to other 925X boards. Abit does include 3 Firewire ports for those who need firewire connections, but the feature set is otherwise straight Intel 925X. There is nothing wrong with this approach as the 925X/ICH6R includes 8 USB 2.0 ports, PCI Express, 4-port SATA RAID with Intel Matrix options, and support for Intel High Definition (Azalia) audio.

Abit has included their typical wide selection of voltages and frequencies to get the most from the AA8 and the Pentium 4 Prescott. Abit was also one of the first motherboard makers to significantly break through the overclocking limitations of the 925X chipset. So, there are some additional automatic manipulations being made by µGuru at boot, where the PCIe frequency is adjusted dynamically in relation to the CPU frequency prior to boot. The overclocking controls are typically Abit, but perhaps the range is a little more limited than we see on other Abit boards. Abit decided not to include PCI Express speed adjustments in the BIOS - they are being manipulated in µGuru instead.

The voltage adjustments that are included in the BIOS have a wider range than you will see on most 925X boards, which will please overclockers who intend to use water or phase-change cooling on the AA8. The important Northbridge adjustments extend from the default 1.5V all the way to 2.05V, which is a wider range than you find on any other board. Abit has added a pretty hefty heatsink with a side-blowing fan to the northbridge to handle the voltage range that they have built into the AA8.

Abit uses a flat edge connector for the single IDE connection provided by the 925X chipset. In most mid-tower cases, we suggest that you connect the IDE cable before you mount the board, since the connector falls under the hard drives in many case designs and is difficult to reach after the board is screwed down. We like the idea of edge connectors, but some case designs make it very difficult to connect the edge-connectors. The floppy connector will not matter to some, but if you use a floppy, you will find the location a real problem, at the very bottom center of the motherboard. When you try to route the floppy cable to clear the 4 SATA connectors, it tends to hide the diagnostic LEDs and interfere with the front-panel connectors. The bulky 24-pin power connector is on the right board edge and 4-pin 12V connector are on the top board edge. Both these locations are excellent in that they will not force you to fish cables over or around the CPU. The Abit trademark 2-digit diagnostic LEDs are also found on the AA8, and we have found that they can be very useful for troubleshooting.

Abit uses the Realtek ALC880 codec with the Intel HD audio on the AA8. This is the same High-Definition audio codec that we see used in most motherboards in the roundup. Realtek says that their 7.1 Channel High Definition Audio features four 24-bit two-channel DACs and three stereo 20-bit ADCs. "The ALC880(D) also achieves 100dB sound quality; easily meeting PC2001 requirements and also bringing PC sound quality closer to consumer electronic devices." You can find more information on the features and specifications of the Realtek 880 at the Realtek website.