Abax Communications Group


Anand Tech
provides in depth computer hardware information, history, testing and reviews with daily updates.

Tom's Hardware Guide
is designed to help and explain all the important hardware aspects of a modern Pentium/Pentium Pro/Pentium II machine. It should be helpful to beginners as well as to experienced computer users to make you able to understand how your computer works and how you can increase its performance.

Failed Links?

If any of these links fail, please take a moment to inform us, and we will update it A.S.A.P.

Not Here?

Please feel free to suggest info that you feel is appropriate for this page.

All logos are the exclusive property of their respective owners. Any use without the expressed written consent is strictly prohibited.

Recent Advancements
820 & 810e   Coppermine & 133 FSB   1 GHz CPU

History of the CPU

Choosing a CPU involves more than just knowing your desired performance and price. There has never been such a large variety of options that can make a particular CPU more powerful than another at specific tasks . Most of these specialized tasks have been achieved by extra help from special features on motherboards. This creates compatibility issues as certain motherboards will only work with a specific type of CPU. There are basically five types of PC CPUs on the general market today.

Socket 7 Slot 1 Super Socket 7 Socket 370 Slot A

Socket 7 CPUs use the same socket as the first generation 586 (Pentium) processors running at 50, 60, and 66 MHz. These first generation 586 CPUs would operate at the same speed as the motherboard (System bus clock). As the manufacturing quality of CPUs increased, they found they could increase the performance by multiplying the operation speed of the CPU (CPU clock speed) while keeping the System bus clock at 66 MHz or lower. This kept motherboard prices down, and would theoretically allow a CPU upgrade without the need to replace the motherboard.

System Bus ClockxRatio=CPU clock speed=MHz Rating

Not all motherboards had a full range of clock multipliers as the faster CPUs may not have been released yet. CPU manufacturers, motherboard designers and developers were still collectively trying to work out intermittent bugs that would cause odd system errors. A crucial component to stability seemed to be the chipset on the motherboard. The quest for a stable chipset churned out numerous types of chipsets. Intel was reputed to have stable chipsets (they make CPUs, so they should know how to make a stable chipset to work with it). This gave motherboard manufacturers a chance to release new products with higher clock ratios, more onboard cache, and advancements to the chipsets.

The Intel Pentium MMX CPU was very different from other 586 CPUs at the time of it's release. MMX offered extra multimedia instructions built into the core of the chip that would save processing time for compatible programs. Some motherboard manufacturers had anticipated that future CPUs would require less voltage, and included a slot on the motherboard to insert a voltage regulator. The MMX CPU operated at a 2.8v voltage which was lower than any other standard CPUs (3.5v to 2.9v). The Pentium MMX CPU still used a socket 7 slot, and it still operated at a 66MHz Bus speed, but the new voltage made it incompatible with most older motherboards without a variable voltage regulator. Unfortunately little to none of these regulators were manufactured. Intel had a new chipset that was rumored to be very stable, so manufacturers who included a voltage regulator slot found it more profitable to make new MMX compatible motherboards than to make the new voltage regulators. Intel had enough influence to have motherboard manufacturers incorporate the 2.8v option into all new motherboards that would also support Pentium, and equivalent Cyrix and AMD CPUs up to 233MHz (3.5 x 66 = 231).

Slot 1 was copyrighted by Intel for their new Pentium II CPU at clock speeds of 233 MHz and above. Other CPU manufacturers were not allowed to make a CPU that would fit in a slot 1 socket. The PII CPU is designed like an old Atari game cartridge with a single edge processor package (SEPP). Why so big? Intel moved the L2 cache memory from the motherboard, to the CPU cartridge for faster access and operation. Cache on 586 motherboards operate at the bus speed (66MHz max), but cache on the PII CPUs operate at half the CPU clock speed. Intel created the LX chipset to manage these innovative changes to the architecture of a motherboard. The PII 333 MHz is the fastest CPU Intel manufactured to work with the LX chipset.

Intel also offered a PII CPU without any cache memory. These cacheless CPUs were called Celeron. The faster PII CPU clock speed architecture made up for the lack of cache memory when compared to 586 CPUs (especially in CPU hungry applications like games). A Celeron running applications like Excel and Access will not perform certain tasks as fast as a full PII CPU with 512k cache. The other recognizable difference between a PII and a Celeron was the price. Without the cache, Intel could sell the Celeron at a fraction of the price of a PII with 512k cache.

The next exciting standard to hit the market was the 100MHz System Bus (Front Side Bus or FSB). Intel released an improved chipset with added motherboard features, and the ability to run at 100MHz System Bus speed. The Intel BX chipset would run PII 350, 400 and 450 MHz CPUs and was backwards compatible with the older PII CPUs (could switch between 100MHz and 66MHz System Bus).

System Bus ClockxRatio=CPU clock speed=MHz Rating

Intel continued to compete in the low end market by adding 128k cache to their PII Celeron CPUs. Intel kept the Celeron(s) running at a 66MHz Bus speed, but were compatible with a BX chipset motherboard for easy upgrading in the future. The clock speeds available for a Celeron with 128k cache in a SEPP configuration were 333, 366, 400, and 433 MHz.

All of this variety pushed many computers down to a sub $1000 price range. Intel was ready for more advancements, but was cautious about overwhelming potential customers with another need to upgrade your motherboard. Intel worked within the specifications of the BX chipset, and released the PIII CPU. The first Intel PIII CPU operated at a 100MHz Bus speed, and CPU clock speeds of 450, 500, 550 and 600 MHz. The PIII offered more multimedia extensions built in, mainly for special internet applications such as plug-ins and compression. If you have a Pentium II BX motherboard, you should be able to upgrade to a PIII, but you may need to upgrade your BIOS. Check with your
motherboard manufacturer.

Super Socket 7 Other CPU manufacturers easily incorporated the multimedia extensions (MMX standard), but were not allowed to use Slot 1 copyrighted by Intel. Intel had stopped production of all Pentium class chipsets and left competitors to eat Intel's dust as they blasted their way off into the 100MHz sunset, but they didn't. Instead, other chipset manufacturers took advantage of this chance to advance the Socket 7 market. Working closely with AMD and Cyrix, VIA and Ali manufactured chipsets that pushed the 66MHz bus speed limit and produced variable 66, 75, 83, 100MHz System Bus solutions. Super Socket 7 motherboards used the same Socket 7 pin grid to keep backward compatibility for older CPUs (including Intel Pentium MMX). You will find that Super Socket 7 motherboards have 512k or more cache memory. AMD offered numerous CPUs to take advantage of such a flexible bus speed and made a low cost 300MHz (100Mhz bus) CPU called the K6-II. AMD also increased the amount of internal cache to their K6-III CPUs (up to 450MHz), and added more multimedia extensions (3DNow!) to compete with the Intel PII and PIII CPUs.

Socket 370 (PPGA) was also copyrighted by Intel for exclusive of Intel CPUs. Cache that used to be either on the motherboard or on the CPU slot 1 cartridge, could now be placed inside the actual CPU chip. New powerful Socket 370 CPUs with internal cache would resemble the size as an old Pentium CPU with extra pin connectors. Celeron CPUs (366, 400, 433, 366, 500, and 533MHz) were made to fit the socket 370 motherboards. The Intel ZX, and ZX-66 chipsets all support a 100MHz System Bus for a Socket 370 motherboard (in anticipation of PIII-Socket 370 CPUs). Socket 370 may look like Super Socket 7, but it will not support Super Socket 7 CPUs. Like Slot 1 architecture, there is no cache memory on the motherboard.

We are now at the chronological moment where many in the industry feel that Intel dropped the ball. Intel announced that they plan to discontinue PIII CPUs in a Slot 1 configuration in favor of the Socket 370 configuration. They then stopped manufacturing the BX chipset while still manufacturing slot 1 PII and PIII CPUs. Intel released the new 810 chipset which has an abundance of onboard features including onboard AGP video which used an optional amount of system memory (since the chipset replaces an AGP video card, 810 motherboards do not have an AGP slot). Most 810 motherboards were the micro type (3 or less PCI and 2 to no ISA). So lets summarize Intel's target market strategy:
  • Discontinue the BX chipset while still manufacturing slot 1 CPUs, thus forcing users to buy motherboards with non-Intel chipsets
  • Introduce chipsets that will only support low-end Celeron CPUs for mainly micro-ATX motherboards that can not support an upgrade AGP video card (such as a 3D-excelerator)
VIA had a chipset that would support slot 1 CPUs, AGP video cards, UDMA66 IDE devices, and 133MHz FSB. The VIA Apollo chipset proved to be remarkably stable and cost effective. The feature-rich VIA Apollo motherboards were even cheaper than old BX motherboards. This continued the demand for slot 1 CPUs and motherboards, and also filled the market that Intel had dropped.

Athlon K7 was AMD's killer CPU and motherboard solution. AMD Designed their own cartridge CPU and the corresponding chipset. The Athlon CPU fit into a slot A motherboard with the AMD-750 chipset which is feature-rich, and runs at 200MHz FSB! With it's 128Kb of L1 cache memory AMD K7-600 outperformed the Intel PIII-600 (32Kb of L1 cache memory). Intel was dethroned as "the King of CPUs" by AMD!

Intel was counting on a new high performance memory, and designed the new 820 chipset to be compatible with the anticipated RIMM memory modules. This would be the chipset that would optimize the new PIII with 256Kb of internal On-Die cache (called Coppermine) family of +500MHz CPUs. Unfortunately, unforeseen problems were occurring when three RIMM modules were used. Release dates were pushed back, and Intel was loosing dominance in the high-end market. Intel began to panic, and started to manufacture the old slot 1 BX chipset again with added features.

PIII Coppermine CPUs were released in a confusing array of slot 1, and socket 370 configurations. To add to the confusion, Intel also released a series of CPUs that operate on a 133MHz FSB in a variety of slot 1, and socket 370 configurations.

Description Core Bus speed Cache Form Factor
PIII 500mhz Katmai 100-MHz 512KB ECC OP Slot 1
PIII 500Emhz Coppermine 100-MHz 256KB ECC OD Socket 370
PIII 533Bmhz Katmai 133-MHz 512KB ECC OP Slot 1
PIII 533EBmhz Coppermine 133-MHz 256KB ECC OD Slot 1
PIII 550mhz Katmai 100-MHz 512KB ECC OP Slot 1
PIII 550Emhz Coppermine 100-MHz 256KB ECC OD Socket 370
PIII 600mhz Katmai 100-MHz 512KB ECC OP Slot 1
PIII 600Bmhz Katmai 133-MHz 512KB ECC OP Slot 1
PIII 600Emhz Coppermine 100-MHz 256KB ECC OD Slot 1
PIII 600EBmhz Coppermine 133-MHz 256KB ECC OD Slot 1
PIII 600Emhz Coppermine 100-MHz 256KB ECC OD Socket 370
PIII 600EBmhz Coppermine 133-MHz 256KB ECC OD Socket 370
PIII 650mhz Coppermine 100-MHz 256KB ECC OD Slot 1
PIII 650mhz Coppermine 100-MHz 256KB ECC OD Socket 370
PIII 667mhz Coppermine 133-MHz 256KB ECC OD Slot 1
PIII 667mhz Coppermine 133-MHz 256KB ECC OD Socket 370
PIII 700mhz Coppermine 100-MHz 256KB ECC OD Slot 1
PIII 700mhz Coppermine 100-MHz 256KB ECC OD Socket 370
PIII 733mhz Coppermine 133-MHz 256KB ECC OD Slot 1
PIII 733mhz Coppermine 133-MHz 256KB ECC OD Socket 370
PIII 750mhz Coppermine 100-MHz 256KB ECC OD Slot 1
PIII 750mhz Coppermine 100-MHz 256KB ECC OD Socket 370
PIII 800Emhz Coppermine 100-MHz 256KB ECC OD Slot 1
PIII 800EBmhz Coppermine 133-MHz 256KB ECC OD Slot 1

820 chipset motherboards were finally released for a slot 1 CPU configuration with an AGP slot. Some were configured to use the standard 168-pin DIMM memory modules to offer an alternative to the high cost of the RIMM memory modules. Demand for 820 chipset motherboards are still low due to their high price. You may be wondering what motherboard could you use for a socket 370 PIII CPU. Enter, the Intel 810e chipset which will support the whole family of socket 370 CPUs. But wait... 810e chipset motherboards still don't have an AGP slot. Did you hear that noise? That was Intel shooting their other foot! If you were an "eager beaver", and ran out to buy a PIII Coppermine CPU in a socket 370 configuration, then you've probably been on a quest to find a stable socket 370/slot 1 adapter card. If you've been patient, then you might-as-well buy a PIII Coppermine CPU in a slot 1 configuration, as it looks like slot 1 will be around for a while.

What an aggressive fast paced race! IBM has thrown in the towel and stopped production of their Cyrix CPUs to focus on other areas of chip development. AMD has committed themselves to competing with the giant Intel (many believe AMD is winning). I have never seen so many hardware revisions and advances in such a short time when the demand and prices for them are so low. What's around the corner? AMD Just released the 1 GHz Athlon CPU!

For more info, see:
Marc Kobayashi
March 7, 2000

Copyright © 2003 Abax Communications Group