As a result of some recent questions on this board (and unfortuantely some people thinking I was attempting to deceive them), I'm going to write an article on the chipsets available for each of the top 2 major processors available today. I'm going to try to avoid making direct performance comparisons between the actual CPUs, as there is plenty of information available on them.
For this article I'll only be considering the available supporting chipsets for the Intel Pentium 4 and AMDs Athlon/Duron/Athlon XP/ Athlon MP. (All AMD processors fit in the same socket.)
Intel Pentium 4 supporting chipsets:_____________________________
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Intel:
i850 - This chipset was the first available chipset for the Pentium 4 and is made by Intel themselves. It is the top performing chipset available for Pentium 4. (Nearly all Pentium 4 benchmarks you will see will be on a motherboard using this chipset.)
i850 strengths - Excellent performance, excellent stability, very good (though not perfect) compatibility with hardware.
i850 weaknesses - Uses expensive Rambus PC800 RDRAM. Rambus ram generally costs 30 - 50% more than regular SDRAM (and DDR SDRAM). The i850 supports only AGP 1.5 V cards. This means that you can only use newer AGP video cards (Geforce 1 or Radeon or newer). Failing to do so WILL result in damage to the motherboard.
i850 other important considerations - Does not support any method for overclocking. Available with both Pentium 4 sockets (socket 423 and 478). Since Socket 423 was discontinued those purchasing Pentium 4 systems in the future DO NOT WANT a socket 423 board, as upgrading the CPU will not be possible. Socket 478 can be easily differentiated from socket 423 as it is very compact in size (much smaller than socket 423). All future Pentium 4s (at least for the next few months) will be socket 478.
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i845 - There are two versions now available of this Intel chipset. All i845 based boards produced until December 21 2001 were only allowed by Intel to use the "ancient" PC 133 SDRAM. Future i845 based boards have now received Intel's permission to enable support for DDR SDRAM.
IT IS OF THE HIGHEST IMPORTANCE YOU AVOID THE SDRAM POWERED VERSION. The Pentium 4 suffers from a severe performance penalty by using PC133 Sdram and this configuration should be avoided like the plague. Benchmarks show the performance difference between the i850 and i845 chipset (with SDRAM) to be 30 - 40%! To give you an idea of what this means; a Pentium 4 i850 based system with a 1.4 Ghz CPU will perform at the same level as a 2 Ghz P4 on the i845!
The brand new i845D that supports DDR Sdram still suffers a performance hit compared to the i850, BUT benchmarks show this to be at a more reasonable 5 - 10%.
i845 strengths - Lower cost of building system because Rambus RDRAM is not used. Very good stability.
i845 weaknesses - Reduced (potentially severe) performance compared to i850 based boards. Only 1.5 V AGP cards are supported (just like i850). Failing to use a 1.5V AGP card will damage the motherboard. Reported PCI bus compatibility issues with some add-on IDE controllers and soundcards.
i845 other considerations - Nearly all OEM (Dell, Compaq, HP, etc) computers use the i845 chipset, as it is MUCH cheaper to build a system with it. Performance of these systems is not good. If you must buy a Pentium 4 based system from a name brand,
get a guarantee it is not using the SDRAM i845! (A P4 1.5 Ghz benchmarks nearly identically to a P3 1 Ghz overall on an SDRAM i845 board.
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i860 - This chipset is nearly identical to the i850, but is specifically for the Intel P4 Xeon and supports dual processors. This chipset only supports a 603 pin socket used only by the Xeon. Motherboards based on this chipset are designed for high end workstations and not desktops, thus the price of i860 boards and the Xeon CPUs are EXTREMELY high.
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VIA:
Important: Intel is suing VIA for producing the following 2 chipsets.
P4X266:
This was the first economical chipset for the Pentium 4. It uses DDR SDRAM, which is much less expensive than Rambus RDRAM (like the i850).
P4X266 strengths - Performance is within 10 - 15% of the i850. Stability of the P4X266 is relatively unknown, as only 2 motherboards are available with this chipset due to Intel legal action. Boards based on this chipset are significantly lower in cost than either the i850 or the i845/i845D. Minor FSB overclocking possible.
P4X266 weaknesses - Not likely to be readily available. Requires the use of VIA 4 in 1 drivers for maximum stability. There is the potential for minor to serious compatibility issues as this chipset is unlikely to be used by any major motherboard manufacturer. Potentially available in Socket 423 and 478 versions. As mentioned before, do not buy a new P4 based system using socket 423 for upgradability reasons.
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P4X266a
The P4X266a is a new P4 chipset produced by VIA. It offers superior performance to the original P4X266, generally within 5% of the i850. Intel is suing VIA over this chipset as well.
P4X266a strengths - Lower cost than either Intel chipset. Much superior performance to i845 or i845D. Similar performance to i850.
P4X266a weaknesses - Unknown stability. Very few available boards based on this chipset, though this is likely to change as VIA themselves are now producing motherboards under their own name.
P4X266a other issues - Requires 4 in 1 drivers. Chipset supports FSB overclocking (though the motherboard manufacturer must also support it.)
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SIS:
SIS 645 - This is the first P4 supporting chipset produced by SIS. It uses DDR SDRAM, but also supports the soon to be released PC2700 (DDR 333) RAM.
SIS 645 strengths - Excellent performance, very good to potentially excellent stability. Lower cost than i850 or i845. Tests with DDR 333 (PC 2700) have shown it to be slightly faster than i850. Fully licensed by Intel for use with the Pentium 4 (i.e. no lawsuits).
SiS 645 weaknesses - This chipset is still new, thus stability and/or compatibility issues are as of yet unknown. SiS has a track record of producing stable chipsets at some cost in performance.
SiS other issues - Support for PC2700 makes this chipset (if it proves to be stable) a highly desirable chipset for the Pentium 4.
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Personal recommendations: Avoid the SDRAM i845 chipset. If you can afford it buy a motherboard based on the Intel i850 chipset, but remember this board requires the use of the more expensive RAMBUS RDRAM. If i850 is too expensive look into the SIS 645, but do some research to see if there are any known compatibility issues, as it is still new. The i845D (DDR SDRAM) is a potentally good chipset, but overpriced for the performance it delivers.
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For more information look at:
http://www6.tomshardware.com/mainboard/01q4/011217/index.html for a performance comparison between all of the available P4 chipsets. (Except i860. ) Notice the terrible performance of the i845 with SDRAM.
Another short article detailing the impact of the i845 is here:
http://www.hardwareanalysis.com/content/reviews/article/1395 Another article is here:
http://www.anandtech.com/mb/showdoc.html?i=1567 Questions and Comments (typos, etc) are welcome. If you find this article helpful, let me know.
