The Giga-Battle Part 2


Last week we brought you the first evaluation of the two Giga-processors from AMD and Intel , using a wide selection of platforms, but unfortunately Intel's latest flagship chipset, the i840, had to be left out. The latest official BIOS of Intel's i840-motherboard 'OR840' wouldn't let any processor run faster than 800 MHz, which to my understanding must be another proof for Intel's paranoia. Obviously Intel wanted to make sure that nobody is able to run processors in the OR840, that could be overclocked to a higher frequency than Intel's fastest processor at the date of the BIOS release. It seems as if the group of BIOS engineers for the OR840 has still not heard of the Giga-Hertz Pentium III, which is why this new processor isn't supported yet. It could also be however, that this group of BIOS engineers is well aware of the non-existent supply of Giga-Pentium IIIs, which is why they can't be bothered to enable OR840 for this processor.

I published this information along with Intel's peculiar statement, saying that systems with Giga-Pentium III are not supposed to ship with Intel's fastest official platform and finally Intel's helpful and knowledgeable German PR-team was able to supply me with an OR840 BIOS that has no 'high speed lock'. Thus I was finally able to run Giga-Pentium III on an i840-platform as well.

Intel 840 Or 'Carmel'

If you should not be too familiar with i840, I suggest you to read my article about this RDRAM-chipset by the name of 'Intel's 840 chipset - The RDRAM Avenger '. However, I will try and summarize the important facts of i840 right here:

  • Code name 'Carmel', bigger and stronger brother of 'Camino' or i820
  • Official workstation and entry-server chipset
  • Designed for RDRAM (Rambus) support
  • Two Rambus channels, resulting in double the memory bandwidth and half the latency (through interleaving) of i820
  • Bandwidth 3.2 GB/s with PC800 RDRAM, 2 GB/s with PC600 RDRAM, no support of PC700 RDRAM
  • Support of PC100 SDRAM with additional MTH-chip, i840 can support up to 4 MTHs vs. only 2 MTHs supported by i820
  • Recently published bug with ECC SDRAM, leading the majority of Taiwanese motherboard makers to drop plans to build i840-motherboards
  • AGP4x - support
  • ATA66 - support

You can see that i840 is a lot more powerful than i820, but it requires at least two instead of only one RDRAM-modules, to populate each Rambus-channel. Intel's OR840-motherboard is a dual processor motherboard with integrated LAN and I guess you can imagine that it does not sport any overclocking features whatsoever.

ECC SDRAM Bug Turns Out To Be I840's Killer

The recently released bug, saying that i840 is supposed to fail with ECC-SDRAM, was almost a killer for this chipset. Due to the high prices of RDRAM and due to the dual-channel architecture, i840 was an attractive solution for an SDRAM platform with 133 MHz FSB-support, using onboard MTHs. i840 was supposed to be used as workstation/server platform, where large amounts of ECC-memory are rather common. After the bug-release i840 ceased to be an interesting platform for systems using ECC-memory, unless the user accepted the high price of ECC-RDRAM. The result was that Taiwanese motherboard makers dropped their i840-plans, because there's only a minority of customers who have enough money to buy large amounts (1-2 GB) of RDRAM for their servers.

Show Me An Intel Platform For Pentium III Xeon Processors At 133 MHz FSB!

You may not be aware of it, but the recent i840 ECC fiasco puts Intel in an even more ridiculous situation when it comes down to platforms for their latest processors. I wonder if you can answer this question. "In which workstation or server platform can you stick a Pentium III Xeon 800EB?" Well, unless you find a Slot2-motherboard with i840 (which doesn't exist to my knowledge), you are pretty much left out in the rain. Intel has currently no server chipset with 133 MHz FSB-support and there are no Slot2-motherboards for 133 MHz FSB Xeon processors from Intel! Intel's 840 chipset was never designed for the high-end server, but only for workstations and entry-level servers. Now since i840 fails to support ECC-SDRAM there is no alternative server chipset from Intel that would support Intel's fastest Xeon-processors. Is that crazy or what? The only alternative is ServerWorks ' ServerSet III chipset, a server/workstation chipset that comes in three different flavors, supporting 133 MHz FSB, PC133 SDRAM, but no RDRAM.

Giga-Pentium III And Intel 840 - A Good Solution?

Well, the answer to that question will end up in an 'if - then' answer.

  • If you don't mind about the high price of RDRAM, then YES it is a solution that's way ahead of i820 as well as any Giga-Athlon-platform.
  • If you don't want to run a BX-platform out of spec at 133 MHz FSB, then i840 is the fastest platform for Giga-PIII.
  • If you don't want to use RDRAM, then you better forget about i840.
  • If you want to run a Giga-Server, you better look at the ServerSet III HE chipset from ServerWorks.
  • If you simply want Giga-performance at an affordable price, you might want to either look at Giga-Pentium III on VIA's Apollo Pro 133A chipset or at Giga-Athlon on VIA's Apollo KX133 chipset instead.

i840's dual Rambus-channel architecture offers a much better performance than i820. We will see in the benchmark results, if i840 is able to outperform 440BX at 133 MHz FSB as well. The results from my latest platform article make that more than questionable though.