VIA, the leading Taiwanese chipset manufacturer, managed to achieve quite a lot during this year. In the first place, we should definitely mention that VIA won about 50% of the chipset market. However, the company didn't slow down its pace and started working in a few other directions. In 2000 VIA began manufacturing its own CPUs and tried to enter the server chipset market. Although the company is known as a developer of mostly low-cost solutions, they selected the right niche when aiming at the server chipset market: small dual-processor home servers and workstations. In other words, this is exactly the field, which had been occupied by only one low-cost mainboard from ABIT - ABIT BP6, based on i440BX and supporting Intel Celeron on Mendocino core in SMP-mode. However you will agree, that this mainboard has become too outdated already, because it doesn't support FC-PGA CPUs and 133MHz FSB. Nevertheless, the demand on solutions like that has always been quite significant, so, VIA decided to try satisfying it. Well, today we will see if they succeeded or not.

Chipset

Via Apollo Pro133A chipset, which is one of the best solutions VIA has ever introduced, supports dual-processor systems. On 29 March 2000 VIA announced its Apollo Pro133A to support SMP-configurations. To tell the truth, VIA didn't have to make any special efforts, because the CE revision of the VT82C694X chipset North Bridge did support dual-processor mode from the very beginning. VIA simply had to make sure that this North Bridge revision worked stably before announcing its new feature to general public.

Therefore the dual-processor VIA Apollo Pro133A has the same features as the single-processor chipset:

Among the chipset key features, which make it much more attractive than its competitors, we should mention the following:

• PC133 SDRAM support. This is the today's most widely spread memory type, which provides the best price-to-performance ratio (we do not consider DDR SDRAM here, since it isn't available in mass yet). As far as the competing products are concerned, i440BX/GX can work only with a slower PC100 SDRAM, ServerWorks III LE requires more expensive Registered DIMM modules, and i840 supports only RDRAM, which drawbacks we prefer not to mention here, since it will take all our time... Unfortunately, DDR SDRAM, which will undoubtedly become an indisputable leader in terms of price-to-performance ratio, cannot now be used in low-cost server solutions, because there are no chipsets supporting both: DDR memory and SMP-configurations at the same time.
• 133MHz FSB support. To our great disappointment, i440BX, which theoretically allows creating cheap SMP-solutions, supports only the CPUs with 66MHz and 100MHz FSB. As for ServerWorks III LE and i840, they do support new high-performance Coppermine processors with 133MHz FSB, however, in this case the cost appears much higher.
• AGP 4x support. You can certainly argue about the importance of this feature for a server, however, we can hardly imagine a high-performance workstation without AGP 4x. i440BX/GX supports only AGP 2x, and ServerWorks III LE doesn't support AGP bus at all. The only chipset other than VIA Apollo Pro133A to support AGP 4x is i840, however, it cannot compensate the drawbacks we mentioned above.

Of course, we can't leave out the fact that VIA Apollo Pro133A chipset doesn't have some features typical of all server solutions. In the first place it is the absence of 64bit PCI support, which is required for high-performance Ultra160 SCSI controllers. Besides, the chipset supports only 1.5GB of memory, which may appear not enough for a fully-fledged server.

Nevertheless, VIA Apollo Pro133A regarded as a chipset for small dual-processor workstations, features everything necessary to play this role and costs just like a single-processor chipset version. Due to this fact, the mainboards based on it are very functional and at the same time very cheap: less then $150.

Well, here everything seems to be quite clear, so, let's pass over to the mainboard.

Mainboard

Today there are four dual-processor mainboards based on VIA Apollo Pro133A in the market. All of them follow one and the same reference design, however, can also boast certain distinguishing features. Here are the mainboards:

• ABIT VP6. Has an ATA/100 RAID controller from HighPoint (HPT370) and a new VIA 686B South Bridge.
• Gigabyte GA-6VXDC7. DualBIOS technology.
• MSI 694D Pro. Has an additional RAID controller from Promise and D-LED diagnostic system.
• Tyan Tiger 133. Supports Slot 1 CPUs.

As you have probably heard, ASUS, AOpen and Elitegroup are also planning to introduce the same products in the near future. But today we are going to speak about a mainboard from Gigabyte, GA-6VXDC7.

   

This mainboard is equipped with two Sockets 370 located in such a way that you can install any cooler, even a very large one, on each of the CPUs. By the way, we would like to remind you that not all the FC-PGA CPUs can be used in dual-processor configurations. For this purpose suit only Pentium III processors of some particular series, with cB0 and cC0 core steppings. Unfortunately, Celeron II doesn't support SMP. As for the older Socket370 Celeron CPUs based on Mendocino core, you can use a pair of them on GA-6VXDC7 mainboard. The table below contains all the series numbers (S-Specs) of the FC-PGA CPUs supporting SMP-configurations:

It has become a tradition already that the CPUs on Gigabyte mainboards are configured with the help of dip-switches. GA-6VXDC7 is also not an exception. When configuring the CPU, you can set the FSB frequency to 66, 100, 112, 124, 133, 142 and 152MHz. However, GA-6VXDC7 doesn't allow changing the CPU Vcore that's why it will hardly be a good choice for an overclocker.

The mainboard is equipped with 4 DIMM slots supporting up to 1.5GB of SDRAM. Like any other mainboard on VIA Apollo Pro133A chipset, GA-6VXDC7 allows setting in BIOS Setup the memory working frequency equal to the FSB frequency or 33MHz higher or lower than the FSB frequency.

The mainboard has 5 PCI slots, 1 ISA and 1 AGP with a special retention mechanism. GA-6VXDC7 can be supplied with an optional Creative CT5880 integrated sound controller. If you look at the photo, you may notice that the distance between the DIMM slots and the AGP slot is quite big, which means that you can install and remove the memory modules with the graphics card plugged in. Unfortunately, no full-size cards can be installed into the ISA slot because of the inconvenient components placement.

Despite two CPU Sockets and a complete set of expansion slots, the size of GA-6VXDC7 hasn't got too big. The mainboard is designed in ATX form-factor and features the following dimensions: 30.4x24.3cm. So, you don't need any special PC cases and the only thing you should really care about is the proper cooling of the case interior.

Of course, GA-6VXDC7 supports Gigabyte's brand DualBIOS technology. There are two flash memory microchips on the mainboard, which store two BIOS copies: primary and reserved. If the primary BIOS gets damaged, the copy allows booting the mainboard and restoring the content of the spoilt chip.

We have to point out that this mainboard is unfortunately supplied with an old VIA 686A South Bridge, which does not support ATA/100. However, nothing prevents Gigabyte from launching a new mainboard modification with VIA 686B South Bridge, because the latter is pin-compatible with its predecessor.

But the most important advantage of this mainboard is of course it price, which makes only $140. Though ABIT BP6 used to cost even less, it supported only Celeron CPUs on Mendocino core. As for Gigabyte GA-6VXDC7, it is a really fully-fledged SMP-solution supporting Pentium III CPUs.

What's The Use Of SMP?

Before passing over to tests and results obtained on our VIA Apollo Pro133A based SMP-system, we suggest discussing briefly the benefits of the dual-processor system and its application field.

The matter is that two CPUs are not enough to get a noticeable gain in performance. Besides that, the OS, which is responsible for distributing the application threads between the processors, should also support SMP-configurations. Unfortunately, the most widely spread operation systems, Windows 95/98, do not support SMP-mode that's why using two CPUs will make absolutely no sense. Among those OS supporting multi-processor configurations we should list Windows NT/2000, Unix clones, BeOS, etc. So check that you have one of them on your PC before hunting for a dual-CPU configuration.

Nevertheless, just an OS supporting SMP may also appear not enough. In order to get a certain performance gain in a particular application, this application should be able to generate parallel calculating threads. If the application is an ordinary one, which uses successive operations and calculations, the SMP will hardly add anything to the overall system performance.

However, if you simultaneously run a few applications supporting no parallel threading on a multiprocessor system with OS supporting SMP, you may still get some increase, though not that high. The operation system will distribute these applications (which it regards as threads) between the CPUs. As a result you will be able to run two and more resource consuming applications on your dual-processor system without any problems. For instance, you may enjoy your favorite game while the second CPU will be busy encoding some MP3 files. Moreover, even several applications being executed at the same time will appear a much easier task for a dual-processor system than for a single-processor one.

Performance

The tests were aimed at discovering the quality of dual-processor support implementation by VIA Apollo Pro133A. To get a better idea of the performance we compared the dual-processor system based on this chipset with that of a system on i440BX from the same price group. Besides, we have also added here the results obtained on single-processor systems based on VIA Apollo Pro133A and i440BX to see the benefits provided by SMP-mode.

In our testbeds we used the following hardware:

• 2 Intel Pentium III 650E FC-PGA CPUs;
• Gigabyte GA-6VXDC7 (Dual VIA Apollo Pro133A), Gigabyte GA-6VX7-4X (Single VIA Apollo Pro133A), Supermicro SUPER P6DBE (Dual&Single i440BX) mainboards;
• 256MB (2x128MB) PC133 SDRAM by Hyundai;
• ASUS AGP-V7700 (NVIDIA GeForce2 GTS) graphics card;
• WD Expert 273BA HDD;
• Microsoft Windows 2000.

Since it doesn't make much sense testing the dual-processor systems in applications, which do not support multi-processor mode, we took only the tests understanding SMP.

In the first place we dwelled on the system performance in Content Creation Winstone 2000. This test measures the system performance in the following applications: Adobe Photoshop 5.0, Adobe Premiere 5.1, Macromedia Director 7.0, Macromedia Dreamweaver 2.0, Netscape Navigator 4.6, Sonic Foundry Sound Forge 4.5, run simultaneously. As a result, the dual-processor system proves faster in this test.

The results show that the dual-processor system based on VIA Apollo Pro133A falls behind the system on i440BX by only 1-2%. Note that the single-processor systems on these chipsets show the same performance difference. All in all, adding a second CPU to your system will provide an 8% performance increase in this test.

Now we are passing over to a more detailed analysis in office applications with the help of BAPCo SYSmark 2000. This test runs a succession of preset actions in 12 standard applications taking the time each application required. The list of applications involved includes: CorelDRAW 9, Microsoft Excel 2000, Dragon Systems NaturallySpeaking Preferred 4.0, Netscape Communicator 4.61, Corel Paradox 9, Microsoft PowerPoint 2000, Microsoft Word 2000, MetaCreations Bryce 4, Avid Elastic Reality 3.1, Adobe Photoshop 5.5, Adobe Premiere 5.1, and Microsoft Windows Media Encoder 4.0. So, SYSmark 2000 allows evaluating the average performance in typical office applications.

The result is just the same as in the previous case. The performance gain provided by adding a second CPU didn't exceed 5-6%. This time the gain appeared a bit lower because SYSmark 2000 runs all applications in a succession, while Content Creation Winstone 2000 - in parallel, shifting between them. Again if we compare the results obtained by our hero with those of i440BX based dual-processor board, the difference will make the same 1-2%.

Moreover, this test allows looking at the performance shown in each separate application and hence estimating the quality of the dual-processor implementation in each particular application:

Well, the results are not that impressive: the only application which took real advantage of the dual-CPU configuration is Windows Media Encoder 4.0. All other applications didn't support multi-threaded calculations at all or supported them just formally.

So that you didn't consider SMP-systems absolutely useless we decided to run one more application, 3D Studio MAX R3, which can boast super successful realization of multi-threaded calculations. The diagram represents the time needed to render Anisotropic Wheel scene supplied together with this program. So, the less time is spent, the better is the result.

We were pleased to find out that the second CPU causes the performance to double! Besides, VIA Apollo Pto133A looks just impressive in this test, showing the performance as fast as that of i440BX.

Besides, we couldn't help testing the performance of dual-processor systems in Quake3 supporting SMP (SMP support is enabled by the terminal command: r_smp 1).

At this resolution the major workload is put onto the system calculating resources (the CPUs), however, adding the second CPU provides only 15% performance increase. It means that Quake3 is not so perfectly optimized for SMP-systems. As for VIA Apollo Pro133A performance, it looks just fine here.

Well, and here it comes! The unexpected result. Adding a second CPU to the system reduces the overall system performance. We can't find any suitable explanation of this sad phenomenon. The only idea that comes to our mind is to blame the graphics card drivers, because it is the graphics subsystem, which is loaded most of all in this test.

In conclusion we checked the quality of the multi-thread implementation on an SMP-system. To do it, we measured the performance of our testing participant in Quake3 at 640x480x16 with a few programs running simultaneously. We considered archiving with WinRAR 2.7 (one of the most powerful compression utilities, which loads the CPU and memory subsystem greatly). There were maximum 4 copies of the utility being executed simultaneously, while Quake3 was running with the default SMP settings (disabled SMP-mode).

As you can see, the advantages of the dual-processor system are indisputable. The single-processor system stumbles with the two WinRAR copies running simultaneously with the game, while the dual-CPU configuration performs on an acceptable level with four archive utilities running in the background mode. Note that in the last case the Quake3 performance on a dual-processor system appeared 6.5 times higher than on a system with a single CPU. We think that now you have got the point of the SMP configurations after taking a look at this test, haven't you?

Stability

Every time we come to speak about multi-processor systems, the stability issue rises. That's why we tested the stability and reliability of VIA Apollo Pro133A based dual-processor system very carefully. And we have to admit that we were satisfied with the results achieved.

Although the first dual-processor systems based on VIA Apollo Pro133A were not the most stable and reliable solutions, now the situation has definitely changed for the better. Probably, the chipset owes a part of this success to AMIBIOS, which is used on Gigabyte GA-6VXDC7 mainboard instead of the ordinary Award BIOS.

Nevertheless, we can't deny the fact that the system based on Gigabyte GA-6VXDC7 proved as stable as the one based on Supermicro SUPER P6DBE (i440BX), which is certainly a great achievement for VIA. That's why from now on you can trust VIA Apollo Pro133A based SMP-systems.

Conclusion

First of all, we would like to say that according to our tests the performance gain due to the use of dual-processor configurations is tangible only in few applications. Most applications support multi-threading just formally that's why the performance grows by only a few percents. However, in case of well optimized applications, such as 3D Studio MAX, the use of the second CPU can double the system performance.

So, the main advantage of SMP-systems appears the "real multi-task support", when the applications running in the background mode do not disturb the active one. If you have been looking for a solution to this problem, then take a look at SMP. Maybe that's what you so badly need.

And now a few words about VIA Apollo Pro133A chipset. It turned out just wonderful, especially for building low-cost dual-processor systems. Performing very close to i440BX and showing high level of stability, VIA Apollo Pro133A proved suitable for use in ABIT BP6 successors.

As for the mainboard we tested, Gigabyte GA-6VXDC7, Gigabyte again proved one of the best developers of not very expensive high-quality mainboards. Therefore, we could recommend this product for those of you who are looking for an SMP-system, especially bearing in mind that this is one of the today's cheapest dual-processor mainboards based on VIA Apollo Pro133A.