The AOpen AK72 is designed around the feature-rich VIA Technologies KX133 chipset. The KX133 is actually comprised of the VT8371 North Bridge controller and the VT82C686A South Bridge controller. All CPU, AGP, and system memory duties are handled by the VT8371 North Bridge, while the VT82C686A South Bridge takes care of the I/O work, as well as ATA-33/66 transfers, quad USB ports, power management, SoundBlaster/DirectSound AC '97 audio, and PC health, voltage and fan speed monitoring. The KX133 fills much the same role in the AMD K7 market as the VIA Apollo Pro 133A chipset does for Intel processors.
Immediately after opening the AOpen AK72 box I started wondering if my recent penchant for reviewing enormous motherboards will ever change. First it was the FIC SD11, then the Asus K7V and now the AOpen K7V. They are all exactly the same size (12”x9.6”) and are definitely at the ultra-high-end in terms of motherboard girth. Although it is a large motherboard, the overall design of the AK72 is very good. The board has a 1 AGP/5PCI/1 ISA format, a well as including an AMR slot for good measure. Three DIMM slots are present, supporting PC100 or PC133 SDRAM, as well as the VCM133 format. There is also a massive arrangement of 2200uF capacitors around the CPU that would make any Asus board jealous.
In terms of Athlon motherboard design, the AOpen AK72 is virtually a text book example of quality engineering. The board ships with the CPU bracket pre-installed and it's also of the “snap-down” variety, which offers smooth installation along with ease of storage later on. Placing the ATX power connector far away from the CPU is another good call. This will enable faster CPU installation and upgrades, while achieving a greater overall cooling effect. While the ATX power connector placement is good, I would have rather seen it farther away from the three DIMM slots.
In a design decision I'm seeing more and more, the floppy and IDE connectors are situated one on top of the other. If you own cables with side-brackets on them, you know what a problem it can be fitting them on boards with IDE connectors adjacent to one other. The three DIMM slots are also easily accessible, and SDRAM modules can be installed even with an AGP card installed. Seeing as the AK72 includes an ISA slot, I was a bit worried about potential issues with the ATX front panel case connectors. Thankfully, AOpen has positioned them adjacent to the AMR slot, so those with full-length ISA cards won't have to worry.