Accelerating Athlon — VIA Releases KT266A Chipset — THG.RU

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VIA Releases KT266A Chipset» —>

No Luck At The First Shot

When VIA finally released its Athlon chipset with DDR-memory support, named ‘Apollo KT266’, in early spring of this year, the new chipset was late and its performance less than impressive. The first DDR-solution for Athlon, AMD’s 760 chipset, had not only been available almost six months earlier, it was also outperforming VIA’s new product. As if this wasn’t bad enough news, SiS had surprised everybody in May 2001 with the release of its SiS735 chipset for the same processor/memory configuration, which was not only cheaper than VIA’s KT266, but also faster. ALi’s MaGiK1 chipset was the only Athlon-DDR solution that was beaten by VIA’s latecomer. Reviewers as well as customers were disappointed. Wasn’t VIA one of the driving forces of ‘Team DDR ‘? Shouldn’t we have reasons to expect more of Taiwan’s largest chipset maker?

Do It Again Sam

VIA was obviously not happy with the performance scores of Apollo KT266. It was one thing to lose against ‘partner’ AMD and its high-cost / high-performance solution AMD760. However, scoring worse than struggling competitor SiS was a shameful defeat that required immediate action. So it didn’t take long after the first reports of the obvious superiority of SiS’s 735 chipset that we heard rumors from VIA officials that a new version of KT266, dubbed ‘Apollo KT266A’, would reverse the painful situation. Several weeks had to pass by until VIA was finally able to substantiate its claims. VIA officials delivered a sample motherboard with the new KT266A chipset to our lab and we checked if VIA’s second try would finally make up for the disappointments of its predecessor.

Apollo KT266A — What’s New?

When you look at the above block diagram of VIA’s new KT266A chipset and compare it to the one of Apollo KT266, you won’t spot a whole lot of new stuff. The only new thing is this black shape painted inside of KT266A’s north bridge, called ‘Performance Driven Design’. This name doesn’t really give a whole lot of insight and it could be replaced with ‘SiS735 Driven Design’ as well. It basically boosts the rather low memory performance of the original KT266 to values that are more than impressive, as you will see below. Let’s have a look at the details provided by VIA:

• Enhanced Memory Controller With Performance Driven Design: The VIA Apollo KT266A features an enhanced memory controller, designed with exceptionally high performance in mind. Supporting DDR200/266 memory, the VIA Apollo KT266A provides lightning fast access to system memory. Timings have been improved, resulting in faster transfers between the synchronized Front Side Bus and Memory Bus. Also, the new memory controller with Performance Driven Design can burst up to eight Quad Words of data per clock, up from four in previous designs. Data queues have also been deepened, allowing faster and access to buffered data. The end result is the industry’s fastest DDR memory controller.
• V-MAP: The VIA Apollo KT266A is part of the family of VIA Modular Architecture Platforms (V-MAP). As a modular solution, the North and South bridge of VIA Apollo KT266A are completely pin compatible with current and future products, such as the VT8233C South Bridge with integrated 3Com(r) Ethernet MAC, and the upcoming KM266 North Bridge with integrated S3 graphics. V-MAP allows flexibility when designing a system around the VIA Apollo KT266A chipset, enabling OEMs and System Integrators to reach different market segments with a single platform.
• High-Speed V-Link Hub Architecture: The VIA Apollo KT266A makes use of VIA’s V-Link Hub Architecture, which provides a dedicated 266MB/s bus between the North and South bridge. Less advanced chipsets use the 132MB/s PCI bus as a link, which must be shared with all PCI peripherals.
• 200/266MHz DDR Front Side Bus Support: The VIA Apollo KT266A supports the AMD Athlon(/Duron( S2K system bus, running at up to an effective 266MHz. Offering up to 2.1GB/s of bandwidth, the 266MHz system bus perfectly complements the high performance DDR memory subsystem and V-Link bus.
• AGP4X/2X Support: Providing up to 1GB/s in graphics bandwidth with AGP4X technology, the VIA Apollo KT266A supports the latest in video card technology. Additionally, it does not sacrifice AGP2X compatibility like less advanced chipsets, allowing low cost graphics products to be paired with low priced Athlon(/Duron( systems.

The list contains two important items. First of all, VIA was finally able to tweak the memory performance of KT266 with the implementation of several improvements of the memory controller. Unfortunately VIA is not giving any proper details, but you will see that the results below speak for themselves.

The other important feature of KT266A is hidden behind ‘V-MAP’. KT266A will be fully pin-compatible with its predecessor KT266, which means that motherboard makers can continue to use the PCBs (printed circuit boards) of the previous KT266-boards. This should ensure very early shipments of KT266A platforms to OEMs and retailers. V-MAP is also allowing the replacement of the current VT8233 south bridge with the VT8233C chip that adds a built-in 100/10 Mbs network MAC. It depends on the motherboard maker and the specs of the board which south bridge will be used.

The Test Motherboard

VIA supplied us with their reference platform VT5577A, which is a Micro-ATX sized board. There is not much to say about the board, except for the fact that it didn’t pose any stability issues or other problems while we tested it.

Benchmark Setup

Benchmark Results

I don’t want to comment too much about the results, because you will see that they speak for themselves. However, before we get into the application benchmark results, I’d like to discuss the scores we saw in Sandra’s memory performance tests, because they are exemplary for KT266A.

Those results speak a clear language. You can see that VIA’s first shot, the Apollo KT266 chipset was providing a particularly bad memory performance, inevitably leading to bad scores in real world applications. The new Apollo KT266A chipset however, is leaving the whole competition far behind, giving a pretty good idea what the results of the application benchmarks will actually look like.

Now let’s skim through the other results without any delaying comments:

Sysmark 2000

Quake 3 Arena

Unreal Tournament

Evolva

Dronez

Vulpine GLMark

AquaNox AquaMark

3D Mark 2001

Alternative Chipsets

We made a little list of all Athlon chipsets with DDR-memory support. We also included NVIDIA’s upcoming nForce chipset, which won’t be available before October 2001 at the earliest.

Except for the yet unreleased nForce420, all competitors of VIA’s Apollo KT266A come with rather similar basic performance features. The theoretical peak memory bandwidths of the Athlon chipsets with single-channel memory controller are all identical. Only nForce420 stands out, due to its dual-DDR channel support.

Summary

VIA has doubtlessly done a tremendous work with the second version of its Athlon DDR-chipset. The performance of Apollo KT266A is nothing short of impressive. It seems as if VIA has finally been able to shake off the image of a memory performance killer. I was informed by VIA spokespeople in Taiwan that the DDR-memory controller of Apollo KT266A is even superior to its counterpart found in VIA’s Apollo P4X266 Pentium 4 chipset. Skeptic people (like me) could of course ask now, why VIA wasn’t able to provide this kind of memory performance in its first Athlon DDR-chipset. There is no doubt that owners of current KT266-motherboards would love to get their north bridges replaced with the new KT266A-chip. Naturally, this is just wishful thinking. However, due to the pin-compatibility between KT266 and KT266A, motherboard makers will be able to start their production of KT266A boards any time, as soon as VIA ships the new KT266A chips. There is no doubt that VIA’s Apollo KT266A chipset has become the most attractive Athlon platform to date.

SiS has all reasons to feel unhappy now. It was able to provide the fastest Athlon-platform for 4 months only. Unfortunately that wasn’t enough time to establish the rather weak brand against VIA in the channel or OEM market. Now SiS will either have to follow VIA’s example and improve SiS735, or hope for success of its upcoming Pentium 4 chipset. It’s a typical example for a failed ‘carpe diem’. SiS did not capitalize on the good reviews of the 735 chipset and now time’s up. It’s a bit of a shame for SiS.

VIA will have all reasons to feel proud and happy now, even though the release of NVIDIA’s nForce chipset is still pending. While KT266A may not be able to keep the performance lead amongst the Athlon DDR chipsets, it will most certainly continue to provide the best performance for the money, as nForce-boards are expected to be rather expensive. The good overall performance of VIA’s Apollo KT266A chipset has now raised the bar for nForce by more than just one notch. The single-channel DDR solution nForce220 should provide at least the same performance as KT266A, while nForce420 and its double-channel DDR design will have to beat VIA’s new product to avoid embarrassments.

Overall we can note another win for AMD’s Athlon and Duron processors, as the release of VIA’s Apollo KT266A chipset just made them faster. Let’s hope that this process will continue with the release of NVIDIA’s nForce chipset. With AMD’s recent price cuts due to its struggle against the clock frequency lead of Pentium 4, informed buyers can now purchase even faster Athlon systems for comparably little money.