Wednesday, May 17, 2000

Introduction

It's with great interest that we've taken on the analysis of the AOpen AX64 Pro motherboard, because it comes from a manufacturer noted for its savoir-faire. The 24K Gold heatsink that adorns the AX64 Pro's Via Apollo Pro133A chipset is testimony of an out of the ordinary board. AOpen's design team has set down a board gifted with "Frequency Isolation Wall", 2200uf Low ESR capacitors, a "Battery-Less" design and "Die-Hard BIOS", to name but a few of the AX64 Pro's chiseled features.

So, with all that excitement awaiting us, let's stop dithering around here, and get to the analysis!

The features

The AX64 Pro is expandable via its 4 PCI slots, 1 ISA slot, single AGP port, and AMR slot. As well it features 3 168-pin DIMM slots that can hold upto 1.25GB of PC100, PC133, or VCM memory. We have to say that this design is still a bit frugal for an age where PCI slots are often plentiful, and wide-ranging. In a perfect world, we'd have liked to see at least 1 more PCI slot on the AX64, just to round things out...

Configuration of the AX64 Pro is accomplished from within the BIOS, as there an no jumpers that are truly required to be set for this purpose. There is one set of jumpers, labeled JP23 and JP29, that can be used to set the PCI bus-to-system ratio, and the host clock minimal operating frequency. To set the CPU's bus frequency, one need only jump into the 'Chipset Features Setup' menu in the BIOS. There one finds a selection of frequencies that ranges between 66MHz and 150MHz. Choice include: 66Mhz, 75Mhz, 83Mhz,100Mhz, 103Mhz, 105Mhz, 110Mhz, 112Mhz, 120Mhz, 124Mhz, 133Mhz, 140Mhz, and 150Mhz.

Another option also allows the memory bus to be run at a frequency 33MHz higher, or lower than that of the main bus.

Last, but not least, it's also possible to adjust the CPU's core voltage from within the very same menu! Available voltages range from 1.30v to 2.05v in steps of 0.5v, and from 2.10 to 3.50 in steps of 0.10v.

The special features

Resettable Fuse

Conventional motherboards use standard fuses to provide minimal protection against power surges, and short-circuits coming from the USB bus and/or the keyboard. These fuses are soldered onto the board, and as such, once they're burnt out, you motherboard is reduced to so much junk unless you unsolder the fuse and replace it. The AX64, though, uses fuses that reset themselves once the surge has ended.

Battery-Less operation

The AX64 also happens to benefit from a design that deactivates the omboard battery while the computer is hooked into the power outlet. The necessary voltage is thus provided by the ATX cable. This is a very effective way to lengthen the battery life.

Die -Hard BIOS 100% virus protection

Recently, viruses such as the CIH have proven capable of destroying the data stored in the BIOS. The AX64 implement a design that doesn't rely on software or BIOS coding for a more effective virus protection. A second emergency-BIOS is made available in order to flash the primary BIOS in case of corruption of the primary BIOS.

"Low ESR", 2200uf Capacitors

The quality of a motherboard's capacitors is very critical to how stable and how well a motherboard will operate. The high-capacity 2200uf capacitors found on the AX64 are Low ESR ( Low Equivalent Series Resistor) ) for greater stability. Placement of capacitors is also critical though, and AOpen has addressed this by placing 7 capacitors close to the CPU, and 4 others nearby the memory slots.

Frequency Isolation Wall

The distribution of a motherboard's components plays a crucial role in how much 'noise' is generated in other nearby components. To deal with this, AOpen has made sure that the traces conducting these signals will be transporting signals of the same order of frequency to reduce the amount of interference and crosstalk with other nearby traces.

24K Gold Heatsink

The 24K gold heatsink located over the Via Apollo Pro133A Northbridge chipset is not only a pretty addition to the AX64's appearance, but it is also quite practical. Gold is not only a fantastic conductor of electricity, but also a terrific conductor of heat. The gold plaque, then, goes along way to helping the chipset heat dissipation; not that motherboard chipsets are big heat generators to begin with but as long as it doesn't hurt... :)

Next: Additional features.