Intel i820 Chipset Review

Introduction

The long anticipated 'Camino' or i820 Chipset still isn't released! Intel's first target was for June 99 and then was pushed forward to September 99. Just days before Intel's planned launch, September 27, 1999, an issue with memory data integrity when more than 2 banks of RDRAM are installed puts a quick stop to the products launch. Tom did the first preview of the i820 chipset set back in June, Preview of Intel's Upcoming 'Camino'-Chipset . Intel was so kind to provide me with a newer sample of the chipset on their VC820 i820 based motherboard. To make my testing more interesting, I've included Intel's tried-and-true 440BX and VIA's Apollo Pro 133 chipsets into my comparison. Given the new features provided by the i820 chipset, I did my best to try and extract the performance benefits each feature has to offer.

What Does The I820 Bring To The Table?

The i820 includes several new features that were implemented to increase bandwidth across the platform. Here is my list of the most important features implemented into the i820 chipset.

HUB Architecture

The i820 is based on the same HUB architecture as the already shipping, low-end i810 chipset. Basically these two chipsets architecture's are identical except the i820 has a 4X AGP bus (without video integration), 133 MHz FSB capability, and RDRAM support. We did two comprehensive reports on the i810 chipset in April 99: Whitney, Intel's 810 Chipset - Part I and Whitney, Intel's 810 Chipset - Part II . To assist in clarifying the new HUB architecture of the i820, I've included a diagram for it and the North / South Bridge based i440BX chipset. As they say: "Pictures are worth a thousand words."

These diagrams demonstrate the i820's advantage with its new architecture. Due to the MCH having direct access to the memory bus, the slow PCI bus does not limit the i820. The i820's UDMA66 support provides twice the bandwidth as the 440BX's UDMA33. However, even the fastest ATA-66 drives can only sustain ~13 MB/s transfer rates.