ASUS SK8V K8T800 Motherboard Review
Socket 940 Platform Featuring VIA's K8T800 Chipset

By: Chris Angelini
January 4, 2004

The ASUS SK8V Motherboard
Think K8V Deluxe with a different socket interface...

The Board:

Armed with the knowledge that AMD's Socket 940 interface won't be around long, you might find it curious that ASUS decided to manufacture more than one corresponding motherboard.  The SK8N, which emerged alongside the Athlon 64 FX-51 is capable enough, after all.  However, as it turned out, VIA's K8T800 chipset is more feature-complete than the nForce3 Pro, fully lending itself to the enthusiast market.  The K8V Deluxe was the first incarnation of ASUS' K8T800 implementation, but it is intended exclusively for Socket 754 processors.  ASUS simply adapted the design of its K8V Deluxe to accommodate a complicated 940-pin interface and dual-channel memory bus to yield the SK8V. 

Of course, the board's 940-pin socket is its most visible feature, supporting Athlon 64 FX and Opteron 100 series processors.  The heatsink retention mechanism used to conjoin processor and cooling solution comes pre-installed, easing setup immensely.  In fact, even though the Athlon 64 FX is complicated and its complementary heatsink heavy, the two can be put together without any tools.  There are four 184-pin memory slots right next to the processor interface.  Each one is color-coded to avoid confusion pertaining to dual-channel operation.  Unfortunately, the board's instruction manual isn't quite as clear, mentioning the registered module requirement only once in passing. Thus, remember to purchase a pair of registered DDR400 modules if you're looking to extract the highest level of performance from an Athlon 64 FX platform. 

In redesigning the K8V Deluxe for dual-channel operation, ASUS was forced to move the power connector from the board's right side to its top, where the 12V auxiliary power receptacle formerly resided.  Fortunately, both power connectors are still oriented to avoid obstructing airflow around the processor.  The K8T800 North Bridge is covered by a small, passive heatsink.  But because it isn't responsible for memory traffic, it merely runs warm to the touch.  Nevertheless, ASUS applies thermal grease between the heatsink and North Bridge to facilitate efficient heat transfer. 

     

Conversely, the VT8237 South Bridge doesn't require any sort of cooling, as it doesn't generate much heat at all.  VIA's South Bridge technology is actually part of what sets the K8T800 apart from its primary competition.  Complete with integrated Serial ATA support, provisions for an advanced audio subsystem, and plenty of peripheral connectivity, it allows ASUS to enable more integrated features without having to pay for discrete components.  Eight USB 2.0 ports are natively supported and exposed through four onboard and four external connectors.  Further, the South Bridge features a pair of Serial ATA connectors that feature RAID 0 and RAID 1 support.  ASUS bundles two data cables and a power extension in the SK8V packaging. 

Beyond the chipset's integrated feature set, ASUS adds Gigabit Ethernet, its own interpretation of onboard audio, a Firewire controller, and additional Serial ATA connectivity.  The 3COM/Marvell 10/100/1000 controller is more than sufficient for home users.  It sits on the PCI bus, meaning it shares bandwidth with the other devices communicating through the North Bridge and suggests the potential for light congestion over VIA's V-Link path, but it's a highly unlikely scenario no matter how many peripherals you've connected. 

     

Even though there is only one chip in the Athlon 64 FX family and five potential candidates in the Opteron lineup, the SK8V's box cover proclaims, "Feel the true power of AMD Athlon 64 FX."  Clearly, ASUS is gunning for gamers with the SK8V.  Considering the number of options for high-quality onboard audio introduced by VIA's VT8237 South Bridge, it's a shame that manufacturers continue to employ shoddy sound circuits while advertising their six-channel onboard audio solutions.  The SK8V boasts an ADI1985 AC'97 codec with six-channel output, yet it suffers a distracting hiss.  We used Sennheiser's MX 500 earbuds to test; undoubtedly, a more high-end headphone or speaker system would amplify the distortion.  Count on buying a discrete sound card if you opt for the SK8V. 

VIA's VT6307 Firewire controller supports a pair of IEEE 1394 ports, one of which is on the board's back panel, while another is available through an included header.  Alternatively, you can connect the designated pins to a front-panel connector if your case sports an I/O cluster for easy access. 

The onboard Promise PDC20378 controller contributes two Serial ATA ports beyond those offered by VIA's VT8237 South Bridge, along with a single ATA/133 connector.  Enabling RAID 0 or 1 support is easy enough through the two Serial ATA connectors; however, setting up a RAID 0+1 array demands a pair of SATA drives and two PATA drives plugged into the ATA/133 port. 

  

  

In order to further differentiate the SK8V from its competitors, ASUS includes several proprietary features on top of the standard hardware package.  The ASUS Wi-Fi slot is one example, providing support for an add-in 802.11b card (available for about $25 online).  It supports 802.11g as well, so when ASUS unveils an updated version of the card, it can purportedly be swapped in without issue. "AI NET", another one of ASUS' touted add-ins, is a marketing term for the 3COM Gigabit Ethernet controller and its accompanying software package that can detect cable faults, similar to a Fluke 620 LAN CableMeter.  Similarly, the "AI AUDIO" feature intelligently detects devices plugged into the 1/8" audio jacks. 

The Bios:

High-end motherboards like the SK8V beg for a flexible BIOS to help unleash maximum performance.  And while ASUS comes up strong with its AMI implementation, the platform itself isn't necessarily receptive to enthusiastic manipulation.  Of course, it includes all of the standard switches for enabling and disabling onboard devices, not to mention AGP and HyperTransport configuration screens.   There are a limited number of options for improving memory performance, though registered memory modules are best left to run at their programmed timings.  ASUS does include an option for enabling three levels of Turbo performance, but none seemed to boot properly. 

The hardware monitoring screen keeps tabs on two temperatures, two fan speeds, and four voltage settings, in addition to enabling ASUS' Q-Fan feature.

     

     

Though it doesn't offer a wide range of overclocking options, the SK8V features fundamental BIOS tweaks like system frequencies up to 300MHz in 1MHz increments.  It also has minor voltage adjustments, including a 150mV VCORE offset, up to 2.8V DDR voltage, 1.7V AGP voltage, and 2.6V V-Link voltage.

Both the VIA and Promise Serial ATA BIOS configurations were easy to set up as well.  They are also both thoroughly documented in the instruction manual, so if you have any problems, check there first. 

Overclocking the SK8V
Or Not...

The Athlon 64 FX is supposed to be AMD's ode to overclocking, complete with an unlocked clock multiplier (there isn't much risk of unsanctioned remarking on a limited edition, $700+ processor, now, is there?). Unfortunately, the first run of review samples were shipped with locked multipliers, and it isn't possible to overclock them by any means other than conventional system bus manipulation.  With that being said, Socket 940 motherboards don't respond well to bus advancements, as they concurrently alter the operating frequency of the HyperTransport and memory buses. 

Using a 209MHz bus frequency and maximized voltages, we were able to hit 2.3GHz with our Athlon 64 FX-51.  Because the sample came from AMD prior to the processor's launch, it wouldn't accept clock multiplier adjustments, making it impossible to gauge the platform's overclocking alacrity.  We've hit 2.4GHz with the same processor using ASUS' SK8N, though, so expect a retail Athlon 64 FX-51 to hit a similar range using a 13x multiplier. 

The 100MHz increase in operating frequency yielded less than two percent additional performance in the Unreal Tournament 2003 Demo and a little more than two percent in 3D Mark03's processor test.

Sandra 2004 and SysMark 2004