AOpen AX6C/AX6C-L ATX Slot-1 i820

As one of the largest motherboard manufacturers in the world, second only to Intel, AOpen has quite a following and an equally great reputation to keep up. With every new chipset release, AOpen has made it a point to remain on top of the release and bring the same quality and reliability to each new motherboard design that has become a tradition from them.

With the release of the i820 chipset, AOpen was put in a very interesting situation. AOpen completed the design of their AX6C months before the release of the i820 chipset, which carried the code name Camino (hence the C in the name AX6C). This design featured 3 RIMM slots for memory expansion, but because of the show stopping bug that caused Intel to pull the plug on the i820 launch, AOpen was forced to delay the release of the AX6C.

It turned out that this show stopping bug was a "layout issue" related to motherboards that featured 3 RIMM slots, and Intel's quick fix for the problem was to limit the amount of RIMM slots to be used on an i820 based motherboard to two. AOpen found this a bit odd and was left with a design, the AX6C, that featured 3 RIMM slots while, at the same time, they were faced with an order from the men upstairs to produce a motherboard featuring no more than 2 RIMM slots.

Keep in mind that the AX6C had already passed AOpen's qualification tests, but according to Intel, there was a stability issue with motherboards that featured 3 RIMMs. Instead of going against the grain and refusing to follow Intel's request, AOpen did the next best thing - they kept the AX6C design which they felt was problem free and added another motherboard to their i820 line, the AX6C-L, that was essentially the AX6C but with only 2 RIMM slots.

While the i820 platform itself is a very expensive one, there is still a demand out there for i820 motherboard solutions, and AOpen isn't a manufacturer to back down from a market with any sort of a demand. They have produced VIA based solutions, are on the verge of releasing an Athlon motherboard, and today, we'll be taking a look at two of their i820 releases, the AX6C and AX6C-L.

New Anand Tech Report Card Rating
92/A-

AOpen AX6C Click to Enlarge

As we mentioned in the introduction, the only differentiating factor between the AOpen AX6C and the AX6C-L is that the latter features 2 RIMM slots, while the former boasts a third RIMM slot.  Therefore, we will only be talking about the AX6C in this review because other than the 2 RIMM slots, the AX6C-L is no different.

The AX6C features what should soon become the standard expansion slot layout on i820 motherboards. As you all know from our review of the i820 chipset, the 801AA I/O Controller Hub (ICH) used with the chipset does not natively support any ISA slots but it can provide for up to 6 PCI slots.

In order for a manufacturer to outfit an i820 motherboard (as well as an i810E motherboard, for that matter) with any ISA slots, they must implement an ISA bridge on the PCB design. AOpen chose to leave out the OEM option for ISA slots on the AX6C and offers the board in a single 5/1/1 (PCI/AMR/AGP) expansion slot configuration. All of the five PCI slots are capable of accepting full length PCI cards as is the AGP 4X slot that is positioned as the first slot from the Slot-1 connector on the motherboard.

AOpen decided to implement a universal AGP connector on the AX6C which supports all AGP 1X, 2X and AGP 4X compliant cards. It is interesting to note that AOpen failed to outfit the AX6C with an AGP Pro connector for delivering more power to AGP cards that take advantage of the 48 new power/ground pins provided for by the AGP Pro specification. Since we have yet to see a retail video card manufacturer step forward and embrace the AGP Pro specification, this doesn't fall into an oversight on AOpen's part, just an interesting point to make.

The layout of the AX6C follows AOpen's usual standard of a clean layout with the exception of one component (all AOpen boards seem to have at least one thing that is out of place), the ATX power connector which is placed on the back side of the Slot-1 CPU connector. The placement of the ATX power supply connector is a very tricky thing for motherboard manufacturers to decide on, and while putting it behind the Slot-1 connector isn't ideal (placing it on the very edge of the motherboard would be ideal) it's better than placing it between the Slot-1 connector and memory slots where it could interfere with the installation of larger heatsinks/fans.