Motherboard guide - Intel
Sections
First Pentium 4s: 1.5-2ghz
The new series: 2Ghz to 3.06 on 133 bus
HyperThreading - the P4 3.06
The last step - 200 bus chips (2.4-3.2Ghz)
Conclusion
Intel Pentium 4
With the Pentium4, Intel took a hefty gamble. They cut down the Pentium4s performance on the basis that they could jump speeds very quickly. In the end, this happened and the big numbers forced AMD to adopt new ratings and probably reduced sales as a result. Its long pipeline requires quick memory for best results. The heatspreader and heatsink attachment result in a stable, uniform heat output despite a tiny core size.The first Pentium4s: 1.5 to 2Ghz
The early Pentium4s came on a 0.18micron size and a 423 pin arrangement. Running only on a 100 bus, performance was low but allowed easy production of chipsets - Via and SIS both designed some as well as Intel's own.Intel 850
Rambus, AGP 4x, USB1.1, UDMA100
Due to the huge requirement for memory performance, Intel took the Rambus controller from the pentium3 series. Rambus is high bandwidth, high latency and always costlier than SD/DDR memory. But it helped bring out the best performance from the early pentium4 chips. It had Intel's trademark stability, as well as a complete lack of adjustments
The biggest problem was cost - it was so expensive - the memory and the board. Few people bought any and few board designs appeared.
Intel 845/D
Single channel SDram/DDR266(D), AGP4x, USB1.1, UDMA100
With a high performance, high cost chipset out, Intel went for the other extreme - low performance, low cost. And low performance is what it was. Due to licensing issues with Rambus, Intel could not produce a DDR chipset until it ran out. As a result, they used the older and marginally cheaper (at first) SDRAM. This seriously starved the Pentium 4 of memory performance and had a huge knock-on effect on processor performance. It became the one for OEMs to use to produce low performance, nice price with good numerical specs(but not actual) to tempt the average guy on the street. It always was and still is one to avoid.
Later the true 845D which added DDR266, but it was short lived due to the 533 bus chips and new socket.
Via P4x266
Single channel DDR266, AGP4x, USB1.1, UDMA100
Intel could not yet release a DDR chipset, so other chipset makers decided to take advantage of this gap between SD and Rambus. Via was the first - actually making it to market before the SDR 845. It proved to be just a notch below the RAMBUS equivalent, but with all the advantages in cost - cheap memory, cheaper motherboards. There was one big blow though - Via were in a licensing situation with Intel, and most big names never used their chipsets because of what Intel may do to them. A sort of big boss situation - they may not send them as many of their own chipsets, or starve them of performance enhancements. Few came out, which was a big shame for Via. They did release an A revision with USB2 and UDMA133, but once again, few used it
SIS 645
Single channel DDR333, AGP4x, USB1.1, UDMA100
Though still relatively expensive at the time, SIS went for the DDR333 route to outdo Via. In the end, it even outdid the expensive Rambus 850. Equal performance, but much lower costs. They did not have any problems with licensing unlike Via, so quite a few boards took it on due to the most lower costs and great performance.
The new series: 2Ghz to 3.06 on 133 bus
With the move to 0.13Micron and the new 478pin socket, Intel could ramp up speeds even more. They also moved to the faster 133 bus, improving potential performance once again. Voltage drops and cooler running meant no real need for change in heatsink design required.Intel 845E/G
Single Channel DDR266/DDR333(G), AGP4x, USB2, UDMA100
With the contract with Rambus over, Intel finally moved onto the DDR chipset. It compared nicely with the competition - single channel DDR333, USB2 and maintained Intel's stability record. The overclockability and stability brought out comparisons with the old BX chipset for Pentium3 chips that scaled right from early 100s to the final 133 versions, with overclockability to spare - an indication of a great chipset.
The complication is that the E version only adds 133 and USB2, only the graphics version G has full support for DDR333. The graphics is entry level to say the least - little possibility of games.
Via P4x333
Single channel DDR333, AGP8x, USB2, UDMA100
Using the Southbridge from the P4x266a, and adding DDR333 support, Via created the P4x333. Little more to add except the licensing issues continued and few adopted the platform. Roughly equal performance with the competition.
SIS 645dx
Single channel DDR333, AGP4x, USB1.1, UDMA100
Initially considered as a simple ddr333 addition to the SIS645, SIS went one better and added 133 support. Aside from these, little changed. It lacked the features of the competition, but usually made up for it in cost. Unofficially, it could even stretch to DDR400 - a big boon for the Pentium4 due to its big demand for memory bandwidth.
SIS 648
Single Channel DDR400, AGP8x, USB2, UDMA133
With the 648 update to the 645, SIS finally caught up with the latest features. It also went one better and added DDR400 support for best memory performance of the time, but it only worked with a single module.
HyperThreading - the P4 3.06
Intel had actually been working on it for some time, but Hyperthreading was not actually enabled until the final processor on the 133 bus. Basically, the software sees the processor as two, so that the pentium4 can make best use of its long pipeline and do many tasks at once. Intel got the upper hand of course - many of its chipsets listed below came out before the competitions alternatives that support HT. At the time, it was not much of a big deal, the 3.06 was extremely expensive.Intel 850e
Rambus 1066, AGP4x, USB1.1, UDMA100
In an earlier attempt to resurrect Rambus from the likes of DDR333 chipsets, Intel updated the 850 to 850e. The first chipset to support HT, it also lacked the competitions features. The high price and limited appeal gave it an early grave. It was the performance leader until the move to 200bus though.
Intel 845P
Single channel DDR333, AGP 4x, USB2, UDMA100
A small update to the 845 chipset happened. The G version which had ddr333 support was given a non-graphics alternative with DDR33 support. HT and USB2 were the only additions.
Intel E7205
Dual channel DDR266, AGP8x, USB2, UDMA100
In an interesting move, Intel made the first ever Dual channel chipset for the Pentium4. The intention seemed to be a replacement for the 850e. And replace it it did, replicating the high chipset cost and limited appeal. This time, it was caused by the fact you can only run in sync, so DDR266 was the only official support. It could not make use of the DDR33/400 chipset now supported by the competition. Overclockers considered it since the performance should rise well with the bus speed, but it proved to be a poor overclocker.
SIS 655
Dual channel DDR333, AGP8x, USB2, UDMA133
5 months after granite bay, the E7205 finally had a successor. The second dual channel chipset for the Pentium4, and it supported DDR333 for more performance than it. With all the latest features (except SATA - still non-existent then) it looked like a winner. However, problems with memory compatibility, particularly timings turned people away. As normal, it is available much cheaper than Intel equivalents.
On a side note, some SIS 648 (single channel) did support HT but no name changes happened.
SIS 658
Rambus 1066, AGP8x, USB2, UDMA133
In another interesting move, SIS produced a Rambus chipset. It is thought that it was designed for people with the elderly 850e that wanted the latest features such as USB2. The problem was that SIS never got it up to full performance and it sat behind even DDR333 chipsets - never reaching the 850e performance. As a result, it was largely not adopted and few people have ever heard of it.
The last step - 200 bus chips (2.4-3.2Ghz)
Intel made a big step with the E variant of the Pentium4 series, re-releasing all the clock speeds again on a 200bus speed, missing out 166 that AMD had used. All supported Hyperthreading, and the bus speed jump made them highly desirable and due to the large speed range, most could afford them. However, the big jump required motherboards that could support the speed, none release yet could officially.Intel 865
Dual channel DDR400, AGP8x, USB2, UDMA133, SATA
With the 865, Intel took the market by storm. All the latest features, amazing stability and great overclocking potential. The ability to run memory asynchronous gave the best performance regardless of processor or to run slower memory at its rated speed. Optional SATA raid gave the enthusiasts what they wanted onboard for no additional expense. There was however two problems - initial cost, and memory compatibility. Though it blew away the competition (sis 655 could only manage ddr333 with few modules) it had problems with early and cheap memory. The more expensive 875 was less picky but demanded a much higher price.
Intel 875
Dual channel DDR400, AGP8x, USB2, UDMA133, SATA
The 875 was the 865 with one extra feature - more performance. Intel devised a way to cut down memory latency. However, most of the Northbridge could not manage it, so Intel simply turned it off and sold it as a 865. This may be the root cause of the memory pickiness, since the 875 is less picky with this feature turned off. Due to the limited number, Intel hiked the price up lots - 875 boards still tend to cost up to ?50 than their 865 counterparts.
Intel 848p
Single channel DDR400, AGP8x, USB2, UDMA133, SATA
The 848p is basically a neutered 865 - single channel memory only. A few 845pe boards were released with handpicked bridges that could make the 800bus, but these were rare and a poor choice due to the cost and the fact they were overclocked. By releasing a true 800 single channel chipset, Intel had the whole market as they covered the value segment as well. There is a big drop in performance of course, but value machines are usually intended for work applications that will benefit little from dual channel memory.
SIS 655tx
Dual channel DDR400, AGP8x, USB2, UDMA133, SATA
In another traditional small model number change, SIS jumped from dual ddr333 on 133 bus and few features, to the matching the 865 chipset. And match in does, to a very small percentage in performance. Few boards are available as yet, but if they can undercut the 865 by a good margin (and they appear to) then they could take the value market by storm. Overclocking is almost as good as the Intel series, but usually slightly below it seems. Some boards have a wealth of async memory settings, so you can run high performance ram without overclocking your processor, if you want to.
Via PT880
Dual channel DDR400, AGP8x, USB2, UDMA133, SATA
The first full licensed Intel chipset from Via, it does well against the competition. Usually slightly below SIS 655tx (probably down to their high-performance bridge interconnect) it basically holds it own well. The SIS chipset is likely to undercut it in price when boards really start arriving, but the VIA name seems to have a higher market impact than SIS. It does not seem to overclock anywhere near as well as the 865 however, despite having a agp/pci lock that most via chipsets lack.
Conclusion
With the pentium4, memory performance is everything. Single channel memory controller impact a severe drop in performance over the dual channel alternatives. As a result, i can only suggest dual channel chipsets.due to the jump to 200fsb, there is no point in suggesting last-generation chipsets for the value market. The sis 655fx is probably the best of them, and though it is rated for 166 they rarely make 200 stably. For the value market, it really has to be the 655tx. Unless Via's pt880 is very cheap indeed, its performance difference and low overclocking threshold and too much of a disadvantage over the 655tx.
For the people with more money, it has to be an Intel chipset. The 865 is a brilliant platform with high overclocking possibilities- many have reached the dizzy heights of 300, and 250 is almost a dead cert. The 875 is however the king of performance due to PATs reduced latency, but you do pay a high premium for it.
SIS 659 - a quad channel Rambus controller - could be a contender, if it actually available. Its 9.6GB/s (dual ddr400 is 6.4) performance could yield benefits. But without actual silicon, no-one can tell.
Last modified: 01/06/2005