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Is This The Best Chipset For The P4?” –>
Pentium 4: DDR333 – Competition for Rambus
The Intel Pentium 4 has a problem: the Rambus platform, based on the Intel 850 chipset, has not enjoyed widespread penetration of the market. Only a few manufacturers have a motherboard with this chipset in their portfolios. Rather, the Pentium 4, fitted with an 845 board and SDRAM, is sold as a complete system by the major chain stores.
It should be clear to everyone that the Pentium 4 cannot reach its maximum performance potential in such systems, unless the user is primarily concerned with pure Megahertz and Gigabyte figures – in which case, all other criteria don’t count. Currently, the better equipped of the Intel PCs even have DDR SDRAM, so that more of the performance potential can be better utilized.
In order to offer an acceptable price/performance ratio, these PCs usually have slow DDR266 modules (with a 2.5 CAS latency), which also get in the way of optimal system performance. So, many enthusiasts go for the Rambus platform, whose memory performance makes use of the Pentium 4’s full potential. A comprehensive test of various platforms with RDRAM can be found in the article Behind The Silicon Curtain: Exclusive Test Of The P4/2666 With 533 MHz Rambus.
Still, the message is clear: Rambus is dead, long live DDR – at least this was Intel’s message at Intel Developer Forum 2002 two weeks ago in San Francisco. SiS offers an alternative chipset to this, based on DDR SDRAM with a 166 MHz memory clock (DDR333), which is meant to take on the Intel Rambus platform with full force.
The Tom’s Hardware lab in Munich brings you an exclusive test of the SiS reference board with the 645DX chipset, which won’t be officially launched until March 13, 2002, at the CeBIT.
The SiS 645DX chipset for Intel Pentium 4 and Socket 478.
As of now, this much can be said: with the 645DX, SiS has a fair chance to make its way onto many motherboards, even before the launch of the Intel 845E on May 21 and the Intel 850E at the end of April.
The Difference Between SiS 645 and SiS 645DX
Schematic architecture of the SiS 645DX chipset: compared to its predecessor, the SiS 645, only the Northbridge has been replaced.
Last December, we tested the SiS 645 chipset, in a comparison with other chipsets for the Intel Pentium 4. Now, the Taiwanese manufacturer has reworked the memory interface and increased the FSB clock to 133 MHz in preparation for the new Pentium 4’s arrival.
All other aspects of the chipset are fully identical – the IDE interfaces continue to work in Ultra-DMA/100 mode, and the USB controller conforms to 1.1 standards. This fact can be determined through the identical Southbridge SiS 961, meaning that Ultra-DMA/133 and USB 2.0 are currently not supported.
An interesting feature set for OEM manufacturers is the graphics, integrated in the Northbridge, which is completely sufficient for simple office applications that involve 2D images. Ambitious users can use a higher-performance graphics card with the AGP slot.
The 6 PCI slots are special features, which also provide full IRQ support. In theory, the memory can be extended to 3 GB, but we can only get clear results on this in a later test with various motherboards. For the entire duration of operation, the Northbridge was notable for its very small increase in temperature, and so, in contrast to products from competitors, it does not require an active cooler.
The manufacturers Asus and MSI plan to come out with SiS 645DX motherboards soon. Asus, for example, will be offering the P4S333.
Reference Board Details
A Tom’s Hardware exclusive: the reference board from SiS with the new 645DX chipset. On the surface, the board looks almost the same as the reference board with the SiS 645 chipset.
The startup screen for the SiS reference board.
Asynchronous memory bus: 166 MHz memory clock (DDR333) for the Intel Pentium 4.
Memory Problem: DDR333 Is Still Rare on the Market
This overview shows the various memory modules and a comparison of their maximum bandwidths.
| Name | Effective Clock Speed | Data Bus | Bandwidth | |
| SDRAM133 | PC133 | 133 MHz | 64 Bit | 1.06 GB/s |
| DDR266 | PC2100 | 133 MHz | 64 Bit | 2.1 GB/s |
| DDR266-Dual | PC2100 | 133 MHz | 64 Bit | 4.2 GB/s |
| DDR333 | PC2700 | 166 MHz | 64 Bit | 2.7 GB/s |
| DDR333-Dual | PC2700 | 166 MHz | 64 Bit | 5.4 GB/s |
| DDR400 | PC3300 | 200 MHz | 64 Bit | 3.3 GB/s |
| RDRAM 400 | PC800 | 400 MHz | 16 Bit | 1.6 GB/s |
| RDRAM 400-Dual | PC800 | 400 MHz | 16 Bit | 3.2 GB/s |
| RDRAM 533 | PC1066 | 533 MHz | 16 Bit | 2.1 GB/s |
| RDRAM 533-Dual | PC1066 | 533 MHz | 16 Bit | 4.2 GB/s |
Comparison: Eight Chipsets for Pentium 4
These table lists all of the chipsets for Socket 478.
| Chipset | SiS 645DX | SiS 645 | Intel 850E | Intel 850 |
| Introduction | March 2002 | November 2001 | June 2002 | January 2001 |
| Processor Plattform | Socket 478 | Socket 478 | Socket 478 | Socket 423/478 |
| Supported CPU | Intel Pentium 4 | Intel Pentium 4 | Intel Pentium 4 | Intel Pentium 4 |
| Multiprocessor Support | no | no | yes | yes |
| Chipset Northbridge | SiS 645DX | SiS 645 | Intel KC82850E | Intel KC82850 |
| Chipset Southbridge | SiS 961 | SiS 961 | Intel 82801 BA | Intel 82801 BA |
| Front Side Bus Clock | 100/133 MHz | 100 MHz | 100/133 MHz | 100/133 MHz |
| Memory Clock | 100/133/166 MHz | 100/133/166 MHz | 400 MHz/533 MHz | 400 MHz |
| Asynchronous Memory Clock | yes | yes | yes | yes |
| FSB-Overclocking | up to 166 MHz | up to 133 MHz | up to 166 MHz | up to 133 MHz |
| max. # DIMM-Slots | 3 | 3 | 4 | 4 |
| max. Memory | 3072 MB | 3072 MB | 2048 MB | 2048 MB |
| SDRAM Support | yes | yes | no | no |
| DDR SDRAM Support | yes | yes | no | no |
| VC SDRAM Support | no | no | no | no |
| RIMM Support (Rambus) | no | no | yes | yes |
| Dual RIMM Support (Rambus) | no | no | yes | yes |
| Ultra-DMA/33/66/100 | yes/yes/yes | yes/yes/yes | yes/yes/yes | yes/yes/yes |
| Ultra-DMA/133 | no | no | no | no |
| Max. # USB | 4 | 4 | 4 | 4 |
| USB 2.0 | no | no | yes | no |
| Max.# PCI Slots | 6 | 6 | 6 | 6 |
| Integrated Graphics | yes | yes | no | no |
| AGP 1x / 2x / 4x | yes / yes / yes | yes / yes / yes | yes / yes / yes | yes / yes / yes |
| ACPI Features | yes | yes | yes | yes |
| Chipset | Intel 845D | Intel 845 | VIA P4X266 | VIA P4X266A |
| Introduction | December 2001 | July 2001 | August 2001 | December 2001 |
| Processor Plattform | Socket 478 | Socket 423/478 | Socket 423/478 | Socket 478 |
| Supported CPU | Intel Pentium 4 | Intel Pentium 4 | Intel Pentium 4 | Intel Pentium 4 |
| Multiprocessor Support | no | no | no | no |
| Chipset Northbridge | Intel 82845 | Intel 82845 | VIA VT8753 | VIA P4X266A |
| Chipset Southbridge | Intel 82801 BA | Intel 82801 BA | VIA VT8233 | VIA VT8233A |
| Front Side Bus Clock | 66/100/133 MHz | 66/100/133 MHz | 100 MHz | 100 MHz |
| Memory Clock | 100/133 MHz | 100/133 MHz | 100/133 MHz | 100/133 MHz |
| Asynchronous Memory Clock | yes | yes | yes | yes |
| FSB-Overclocking | up to 166 MHz | up to 180 MHz | up to 180 MHz | up to 180 MHz |
| max. # DIMM-Slots | 3 | 4 | 4 | 4 |
| max. Memory | 2048 MB | 2048 MB | 4096 MB | 3072 MB |
| SDRAM Support | no | yes | yes | yes |
| DDR SDRAM Support | yes | no | yes | yes |
| VC SDRAM Support | no | no | yes | yes |
| RIMM Support (Rambus) | no | no | no | no |
| Dual RIMM Support (Rambus) | no | no | no | no |
| Ultra-DMA/33/66/100 | yes/yes/yes | yes/yes/yes | yes/yes/yes | yes/yes/yes |
| Ultra-DMA/133 | no | no | no | yes |
| Max. # USB | 4 | 6 | 6 | 6 |
| USB 2.0 | no | yes | no | yes |
| Max.# PCI Slots | 6 | 6 | 5 | 5 |
| Integrated Graphics | no | no | no | no |
| AGP 1x / 2x / 4x | yes / yes / yes | yes / yes / yes | yes / yes / yes | yes / yes / yes |
| ACPI Features | yes | yes | yes | yes |
Test Setup and Details
| Intel Hardware Socket 478 |
|
| Processor | Intel Pentium 4/2000 MHz (400 MHz QDR FSB) |
| Motherboard | |
| VIA P4X266A | VIA reference board P4X266A, Revision: unknown Bios: P4XBS09p Date:15.11.2001 |
| VIA P4X266 | Shuttle AV40V12 Revision: 1.2 Bios: AV40902E Date: 05.09.20001 |
| Intel 850 | ASUS P4T-E Revision: 1.00 Bios:1005 BETA 002 Date: 11.12.2001 |
| Intel 845 | MSI 845 Pro Revision: Bios: 1.0B7 Date: 03.08.2001 |
| Intel 845B | ASUS P4B266 Revision: 2.01 Bios: 1003 Date: 06.12.2001 |
| SiS 645 | SiS 645 reference board SS51A Bios: 645p14k9 Date: 19.09.2001 |
| SiS 645DX | SiS 645DX reference board SS51B |
| Memory 1 | 2 x 256 MB, RDRAM, 400 MHz, Viking |
| Memory 2 | 512 MB, DDR-SDRAM, 166 MHz, CL2.5, Winbond |
| General Hardware | |
| Graphics Card | GeForce 3 Memory: 64 MB DDR-SDRAM Memory clock: 400 MHz Chip clock: 250 MHz |
| Hard Drive | 40 GB, 5T040H4, Maxtor UDMA100 7200 rpm 2 MB Cache |
| Drivers & Software | |
| Chipset Driver (Intel) | 3.20.1008 |
| Chipset Driver (VIA) | 4in1 – V4.35 |
| AGP Driver (SIS) | V1.09 |
| Graphics Driver | Detonator 4 Series V23.10 |
| DirectX Version | 8.1 |
| OS | Windows 2000 SP2 |
| Benchmarks & Settings | |
| Quake III Arena | Retail Version 1.16 command line = +set cd_nocd 1 +set s_initsound 0 Graphics detail set to ‘Normal’ Benchmark using ‘Q3DEMO1’ |
| SiSoft Sandra 2001 | Professional Version 2001.3.7.50 |
| Newtek Lightwave | Rendering Bench SKULL_HEAD_NEWEST.LWS |
| mpeg4 encoding | Flask X4.2A DivX 4.11 Compression: 100 Data Rate: 1500 Kbit Format: 720×480 Pixel@25 fps no Audio |
| Studio 7 | Version 7.07.1 (MPEG 2) |
| Sysmark 2001 | Patch 3 |
| Lame | Lame 3.89 MMX, SSE, SSE 2, 3DNow |
| WinACE | 2.04, 178 MB Wave file, Best Compression, Dictonary 4096 KB |
Benchmarks Under Windows 2000
We wanted to avoid the automatic resource management feature integrated in Windows XP, so, as in the past, we opted to use Windows 2000 to test this group of chipsets. The only reason for choosing Windows 2000 over Windows XP is that the newer version of Windows optimizes how background applications run. This new feature would have prevented us from obtaining accurate benchmarking results.
| OpenGL Performance | Quake 3 Arena ‘Demo 1’ and ‘NV15 Demo’ |
| 3D Rendering | SPECviewperf ‘Light-04’ |
| 3D Rendering | Lightwave 7b |
| DirectX7 Performance | Unreal Tournament |
| MP3 Audio Encoding | Lame MP3 Encoder |
| MPEG-2 Video Encoding | Pinnacle Studio 7 |
| MPEG-4 Video Encoding | XMpeg 4.2a and Divx 4.11 |
| Office Performance | Sysmark 2001 |
| Archiving | WinACE 2.04 |
| SiSoft Sandra 2001 | CPU and Multimedia Bench |
We used a total of 16 different benchmark tests in order to obtain the most complete, well-balanced view of how the SiS 645DX performs. Benchmark results from a total of seven different platforms for Intel Pentium 4 give you a clear overview. The main question here is this: can the SiS 645DX with DDR333 reach the level of Intel 850 with Rambus?
We ran four different Quake 3 tests to determine OpenGL performance. The different MPEG-encoding benchmarks provide a comprehensive testing environment – the Lame MP3 Encoder was used to encode a 178 MB WAV file into MPEG-1 Layer 3 format. Still an established standard, our MPEG-4 test converts a file from a commercial DVD-ROM into MPEG-4 format using Xmpeg 4.2a and the Divx 4.12 codec. We also created an MPEG-2 film using the video-editing software ‘Pinnacle Studio 7’. A regular in our list of benchmarks is determining rendering performance using Newtek’s Lightwave (version 7b). We also ran WinACE 2.04 to test file archiving, a standard and practical application in the computing world. In order to determine office performance, we used the new Sysmark 2002 benchmark. SPECviewperf provides a comprehensive suite of 3D benchmarks.
Clock Speeds of Individual Test Platforms
OpenGL Performance: Quake 3 Arena
In the four timedemo runs from Quake 3 Arena, the SiS 645DX with DDR333 clearly beats the Rambus platform with Intel 850. The weakest performer was the Intel 845 with SDRAM memory, a configuration that is frequently found in the complete PC systems that are sold.
DirectX 7- Performance: Unreal Tournament
At lower resolutions, the SiS 645DX claims the top spot, while the Intel 850 with RDRAM pushes ahead of it at higher resolutions.
MP3 Audio Encoding: Lame MP3
The Lame MP3 Encoder was used to convert a 178 MB sound file from a WAV format to the MPEG-1 Layer 3 format. The graph shows that the SiS 645DX and the VIA P4X266A take the leading positions.
MPEG-4 Video Encoding: Xmpeg 4.2a and Divx 4.11
Memory performance is an important factor in MPEG-4 encoding. The record-holder is the Intel 850 chipset in combination with RDRAM. Following on its heels is the SiS 645DX with DDR333 and its very respectable frame rate.
SiSoft Sandra 2002 Benchmarks: CPU and Multimedia
In SiSoft Sandra 2001, Intel 8450 with 400 MHz RDRAM shows that it provides the highest memory performance. Still, the SiS 645DX places second in all of the tests – only its memory performance was somewhat weaker.
3D Rendering: Newtek Lightwave 7b
Surprising results with the Newtek Lightwave benchmark: the SiS 645DX and the VIA P4X266A tie for first place. The Intel 850 with RDRAM is only slightly weaker.
Archiving: WinACE 2.04
Archiving is a very practical application. WinACE 2.04 was used under Windows 2000 to archive a 178 MB WAV file while the clock was running. The results are clear: the SiS 645DX clearly trounces all of the other platforms. Here, the high I/O performance of the SiS 645DX pays off, as does its high-speed memory.
MPEG-2 Video Encoding: Pinnacle Studio 7
In creating an MPEG-2 video with Pinnacle Studio 7, the SiS 645DX with 166 MHz memory is significantly faster than the competition. The slowest candidate is the Intel 845 with SDRAM.
Office Performance: Sysmark 2001
In the office benchmark, the SiS 645DX lands just a nose behind the Intel 850 platform, taking second place.
3D Rendering: SPECviewperf (Light-04)
In this OpenGL benchmark, the SiS 645DX with DDR333 memory clearly outperforms the Intel 850 with Rambus.
Conclusion:
SiS 645DX with DDR333 Beats Intel 850 with PC800
In this comparison of various P4 platforms, the results are surprising: in 10 out of 16 benchmark disciplines, the SiS 645DX outperforms the Intel 850. In particular, the new chipset is notable for its high I/O performance, and in addition, is accompanied by a low CPU load. The impressive benchmark results attest to the fact that the Taiwanese manufacturer has reworked the memory interface of the Northbridge.
And don’t forget: in contrast to its rival VIA, who does not have a license from Intel and offers its chipset almost illegally, SiS has made all the necessary contractual agreements. This clears the way for SiS to take on the mass market, which has waited a long time for an alternative to the expensive Intel 850 plus RDRAM.
SiS is ahead of the game by about two months, or at least until Intel brings out its 845E with 133 MHz support. Nevertheless, it must be said that it is only when used together with special DDR33 memory that the SiS 645DX reaches the performance levels measured in our tests and poses a real threat to Rambus. It remains to be seen how the price for DDR333 modules (CL2.0) will develop, because currently, RDRAM (PC800) can be had for the same price as DDR266 (CL2.0). Because of pricing considerations, a few OEM manufacturers will combine the SiS 645DX with DDR266 (CL2.5), so it will no longer be ahead in terms of speed.
Those who buy SiS boards will have to do without a few of the latest features: the current Southbridge only supports Ultra-DMA/100 as well as USB 1.1. In the future, support for ATA/133 and USB 2.0 would be an advantage.
Asus and MSI stand ready to offer the first boards with SiS 645DX. With this chipset, SiS offers a convincing component that will hopefully be available on the market very soon. The competition from VIA faces an uphill struggle – motherboard manufacturers are wary of offering a board with a component that is not officially approved of by Intel, and is subject to ongoing litigation.
