BlueSmoke - Review : AOpen AK77 Plus

		Date	: Dec 24th, 2001
		Category	: Motherboards
		Manufacturer	: AOpen
		Author	: Jin-Wei Tioh

The Socket-A platform is ever popular, and ever expanding, with AMD gradually adding to the list of processors. Now, numerous chipset manufacturers have brought DDR to the platform; ALi with the ALi MAGiK1, VIA with the KT266 and KT266A, SiS with the SiS735, and AMD with the AMD760. While the initial revision of the MAGiK1 was targetted at the value segment of the market (eg. the ECS K7AMA), the solutions from VIA, SiS and AMD generally offer higher performance.

In our first Socket-A DDR motherboard review, we take a look at the AOpen AK77 Plus. Note that there are two versions of the motherboard, differentiable only by part numbers; one is based on the KT266, the other on the KT266A. The evaluation unit we received was the KT266 model. Without further ado, let's examine the AK77 Plus' brief technical overview :

The highlights of the AK77 Plus are its packaging, black PCB, two ATA-100 RAID headers and hefty size of 12" x 9.5" (HxW). The packaging has a cutout "window", giving a peek at the contents within. The motherboard, cables, documentation and CDs are all encased in a plastic clamshell case with an emblazoned AOpen logo, clearly showing AOpen's intentions to bring attention to their product. About the only other motherboard we've seen in similar packaging is IWill's KK266 (powering the system of yours truly).

As with the other two AOpen motherboards that have been evaluated, the AK77 Plus is a hefty package of electronics, which may cause some amount of grief (usually it's removing all 5.25" devices) for end-users with small cases. Component placement this time around is excellent, with one minor gripe. The power supply connector sits close to the right edge of the motherboard, parallel to the DIMM slots. While being appropriate, since it means that the power supply cables would not run over the CPU, the connector is a mere 0.25" away from the DIMM slots. With the average human finger being 0.3" thick, unplugging the power supply cable could present a minor problem.

The DIMM slots are about half an inch above the AGP slot, making DIMM installation/removal a non-issue. On some motherboards such as the ASUS TUA266, it is necessary to first remove the AGP card before installing / removing DIMMs.

AOpen again decided to integrate only 2 USB ports, including 2 additional headers on the board as well as a bracket to provide another 2 USB ports. The second and third USB headers are placed parallel in between PCI slots, an ideal arrangement for case modders and those with cases having lower-front USB ports, such as the SkyHawk aluminum line. As done on most motherboards, the front panel connectors are placed in the lower-left corner of the motherboard, ensuring that the cables do not get in the way of any expansion slots.

The regular IDE, ATA-100 RAID and floppy connectors are located right at the bottom of the motherboard, roughly half an inch from the DIMM slots. This minimizes potential cable clutter because the headers are closer to the storage devices. Another plus is that the cables do not obstruct the airflow to the CPU, which helps with overclocking. Unlike the AX3S Plus (a Socket-370 RAID motherboard), the RAID headers do not obstruct any slots. Every single slot on the AK77 Plus is able to accommodate a full-length card, a commendable layout achievement.

Capacitor placement alright, though 3 2200uF units can stand to be placed a little further from the CPU socket. Another point that we have thus far neglected to highlight is the "no amount zone" specified by AMD. Both the AK77 Plus and AK73 Pro (A) (which we previously reviewed) follow this specification, enabling the usage of heatsink/fan units which use the 4-lug mounting system, such as the Zalman CNPS5000 and the Swiftech MC462A.

The VT8366 North Bridge, the core of the VIA KT266 chipset, sits between the CPU socket and the AGP slot, roughly an inch from each. It provides all the major features of the chipset, namely DDR, 100/133MHz FSB as well as AGP 2x/4x support. While a new chipset is obvious, what is not so obvious is the introduction of V-Link, VIA’s answer to Intel’s two year old IHA (Intel Hub Architecture). Previously, most north and south bridges were interconnected via the 33MHz PCI bus, offering a peak bandwidth of 133MB/s to be shared between the two bridges as well as all other PCI devices (eg. ATA controller, NIC, sound card). V-Link doubles the signalling rate to 66MHz, thereby doubling the peak bandwidth offered (266MB/s) to accommodate modern high-bandwidth consumption interfaces such as USB 2.0 and FireWire. AOpen opted to forgo their previous passive cooling solutions in favor of a sharp looking, silver AOpen chipset cooler, making the addition of a fan or Blue Orb unnecessary.

The AK77 Plus comes equipped with a universal AGP slot, which means that it is not keyed specifically for AGP 2x or AGP 4x cards. Additionally, AOpen has added a locking mechanism at the end of slot which helps secure the AGP card in place. It is basically a small plastic clip, working similarly to that of a DIMM slot by clipping onto the small tab on the AGP card. While it would take quite an amount of force to unseat the AGP card (an amount that would likely have damaged other components more severely), it is a small, but welcome feature.

Like most motherboards on the market, the AK77 Plus sports 3 DIMM slots for a maximum memory capacity of 3GB. At any FSB range, you have the option of running your RAM at either 3X or 4X PCI clock. This makes for an interesting point for those who want to run a 133MHz FSB CPU, whilst maintaining their older PC1600 DDR SDRAM.

The VIA VT8233 South Bridge basically boasts support for Ultra-ATA 100 and 6 USB ports, on par with all other chipsets. Some interesting features include support for 6-channel AC'97 sound, and the VT8233's integrated 10/100 BaseT Ethernet and 1/10 Home PNA controller. While AOpen chose not to implement these more advanced features, it is certainly interesting to see the move towards everything being integrated. For expansion slots, AOpen chose to go with the more OEM oriented 1/5/0/1 (AGP/PCI/ISA/AMR) configuration, something which ASUS also decided to do on their A7V266. As mentioned earlier, all the slots on the AK77 Plus are capable of accommodating full-length cards.

The AK77 Plus features an impressive capacitor count; 3 3300uF, 12 2200uF, 2 1200uF, and an assortment of smaller capacitors. 6 voltage regulators with large honking heatsinks sit adjacent to the CPU socket. As with both the AK73 Pro (A) and AX3S Plus, AOpen employs one of their techniques in achieving stability - better distribution of capacitance. They utilize a greater number of lower capacitance low ESR (equivalent series resistance) capacitors. Hence, while the total capacitance may be the same, it is distributed more evenly throughout the motherboard.

To further enhance stability, the AK77 Plus was designed with the "Frequency Isolation Wall". AOpen attempts to separate the motherboard into regions, where each region is running at similar local frequencies. This serves to minimize signal interference via cross talk which is an unavoidable occurence in electronic circuits. They also took the pains in calculating the trace lengths and routing to ensure that traces operating at the similar clocks have equivalent lengths, minimizing clock skew.

In the overclocking department, the AK77 Plus features a jumper for FSB range selection (ie. either 100-132MHz, or >= 133MHz), adjustable in 1MHz increments via the BIOS. The FSB clock generator used is capable of a whooping, no insane 248MHz! CPU core voltage is fully jumperless, allowing adjustments from 1.1V to 1.85V in 0.25V increments. CPU multiplier selection is done via DIP switches. However, VIO and DIMM voltage adjustments are absent. We'll find out how the absence of these two features affect the AK77 Plus' overclockability. The CPU fan header held up well when paired with a black-label Delta fan.

As is the standard practice nowadays, AOpen opted to integrate AC'97 audio. Once again, they chose the no frills Analog Devices AD1885 CODEC, the same CODEC used on the AK73 Pro (A) and AX3S Plus. For casual use, the integrated audio performs acceptably, with processor use not noticeably slowing down the system. However, for more intensive uses, such as DVD playback or gaming, it is definitely better to go with a hardware-based sound card as they generally hog less CPU time while providing more audio functionality and better sound quality.

The AK77 Plus is equipped with a Promise PDC20265R ATA-100 RAID controller, which supports RAID 0 (striped) and RAID 1 (mirrored) arrays. If you elect not to use the RAID functionality, the Promise FastTrack 100 Lite also doubles as a second IDE controller, supporting two more IDE channels (4 devices). This makes for a grand total of 8 IDE devices, certainly more than enough to overwhelm just about any case.

Another standard feature on AOpen motherboards are the Dr. Voice, Dr. LED and Die-Hard BIOS technologies. Dr. Voice is a diagnostics tool, audibly telling you what is wrong with your motherboard in 4 languages; English, German, Chinese and Japanese. Dr. LED, an optional accessory, is a set of 8 LEDs, which indicate which part of the motherboard might be having problems. Finally, the Die-Hard BIOS technology helps to protect your system from virus attacks or failed BIOS updates. Essentially, there are two BIOS chips on the motherboard, with only the primary chip being active during normal use. Upon corruption of the primary chip's contents, the machine will switch over to the secondary chip.

To round out the bundle, AOpen includes a product registration card, their superb "getting started" poster with the basic instructions on how to setup the motherboard and 2 CDs; one with an electronic version of the manual, the drivers and utilities; the other with a full version of Norton Antivirus 2001 for Win9x/NT/2000. This saves the end-user the time, money and inconvenience of separately purchasing an antivirus program. The package also contains two detailed manuals, one for the AK77 Plus, and the other for the onboard Promise RAID controller. So far, AOpen's motherboard manuals describe the product and related technologies / terminologies in detail but lack any descriptions and explanations of the BIOS settings. The RAID manual however, is very in-depth, providing more than enough information on how to setup and maintain a RAID array.

We'll let the AK77 Plus cut its teeth on our standard suite of benchmarks...

For the results below, the AK77 Plus was run with standard parameters (ie. no overclocking) at 800MHz (6 x 133 FSB), CAS 2. Please note however, that you shouldn't compare the results obtained here to rate a Socket-370 motherboard and vice versa.

We would like to take a moment to thank the sponsors that have made this review possible. The Thermoengine was supplied by ThermoSonic Technology, the Artic Silver II TIM by Arctic Silver LLC, and the Siluro MX400 by ABIT.

In addition to tests using standard parameters, we performed overclocking tests to ascertain the highest FSB speeds the system could sustain. We started by setting the CPU (a pencil-unlocked Duron 800) to run at 133MHz FSB with a multiplier of 6 (for a speed of 800MHz) and verified its stability via informal testing using Ultra-X's RAM Stress Test, Stability Test and HotCPU. The FSB was gradually increased the tests repeated. All tests were done BIOS default memory settings with the CAS latency set to 2.5, to minimize the chances that the RAM was the limiting factor. Ultra-X makes some of the best professional PC diagnostic tools on the market, and quite a number of people use them on a regular basis including some of our acquaintances. Their RAM Stress Test has proven quite effective in ferreting out any memory instability problems, which is one of the things that is evaluated when increasing the motherboard's FSB.

As mentioned earlier, the clock generator on the AK77 Plus is capable of cranking out 248MHz. We reached the stability limit at a cool 157MHz, with the processor running at 785MHz (5 x 157). This is a full 19% increase in FSB frequency, no slouch by any standard. The lack of VIO and DIMM voltage adjustments clearly has no bearing on the AK77 Plus' overclockability, though it begs the question : How much harder can it be pushed with these adjustments?

The good :

• Great aesthetics with the black PCB.

• Active chipset cooling solution. Aesthetics are not sacrificed with the stylized, silver colored heatsink.

• As stable as it gets under both standard and overclocked (157MHz FSB) conditions.

• Excellent layout, save for the slightly close 2200uF capacitors. All expansion slots are capable of accommodating full-length cards, IDE, RAID and floppy headers are placed to minimize cable clutter and maximize airflow to CPU.

• Observes AMD "no mount" zone, with support for heatsink/fan units such as the Zalman CNPS5000 and Swiftech MC462-A.

• Quite user friendly, with clear installation instructions in the form of a "getting started" poster. Additionally, it also has good diagnostic capabilities, with the Die-Hard BIOS and Dr. Voice. The optional Dr. LED should make it even better.Nice software bundle, which includes Norton Antivirus 2001 for Win9x/NT/2000.

...and unfortunately the bad :

• KT266 based. The newer KT266A-based model of the AK77 Plus should offer equivalent overclockability plus higher memory throughput.

• Overclocking is not so convenient, as you have to manually set the CPU multiplier via DIP switches. Although FSB speed is adjustable in the BIOS, you still have to set a jumper to select the FSB range. Lack of VIO and DIMM voltage adjustments, although that didn't stop us from pushing the AK77 Plus to 157MHz.

• Expansion slot configuration of 1/5/0/1 (AGP/PCI/ISA/AMR). Although 5 PCI slots are sufficient for most users, 6 PCI slots would have been even better. While being beneficial to OEMs, the lack of AMR peripherals virtually renders the slot a waste of space.

• Integrated AC'97 audio. While offering acceptable audio quality for casual usage, most users will end up disabling it in favor of a true hardware-based audio solution. Removing the AC'97 CODEC and other associated audio hardware might have reduced the cost of the motherboard.

• Size isn't everything. This thing is a behemoth that might cause problems for those with more compact casings.

In conclusion? The AK77 Plus does not disappoint in the stability department, not exhibiting any weird USB timeouts under the FreeBSD makeworld test, and being able to take the punishment of a 157MHz FSB without a single crash. Component layout is well done, with all slots capable of accommodating full-length cards, and the inclusion of onboard RAID at a competitive price is a boon to the end-user. Performance is excellent, at least that which can be expected from the KT266 chipset. To top these off are the excellent Dr. Voice and Die Hard BIOS technologies, the nice software bundle and the good documentation (save for the BIOS settings). Lastly, there is the sexy black PCB and stylish silver AOpen chipset heatsink/fan unit. However, there are two main shortcomings to the AK77 Plus. VIO and DIMM voltage adjustments are absent, but fortunately don't seem to inhibit the its overclockability. The use of DIP switches to control the CPU multiplier is an incovenience, and should have been implemented in the BIOS as with AOpen's own AX3S Plus. Also, while a 1/5/0/1 (AGP/PCI/ISA/AMR) expansion configuration is enough for most users, power users would have preferred to do away with the onboard sound and the AMR slot, replacing it with an additional PCI slot or an ISA slot for legacy support. If you want a perfectly functional work of art, the AOpen AK77 Plus gets our hearty recommendations for a KT266-based motherboard. However, you might want to hold back for its KT266A-based brother (which we hope to evaluate soon). Recommended!