The pathways in your PC are more like back roads than superhighways, but new construction is under way. Emerging technologies such as AGP 8X, serial ATA, and PCI Express will help make room for more-advanced applications on the desktop.

Longtime PC users know better than to get too attached to their systems. Before you realize it, the technology in your desktop is outdated and too slow for the latest and greatest components and applications. Worse yet, some technologies simply fade away, making peripheral upgrades impossible--look at what happened to ISA and VL-bus expansion slots. Well, get ready for not one, not two, but three new technologies for desktops that will render your current PC obsolete.

AGP 8X
The first of the new technologies that you are likely to see is AGP 8X, the final speed step for the accelerated graphics port before it too starts fading away in 2004 (see PCI Express below). A single expansion slot on a system motherboard, AGP provides a fast and direct connection between a graphics card and system memory. AGP 8X supports a potential throughput of more than 2.1GB per second--twice the speed of today's AGP 4X solutions.

There are already a few AGP 8X graphics card on the market now, such as the ATI Radeon 9700 Pro. Both Via and SIS include AGP 8X support in their latest chipsets, as does Nvidia in its new nForce2 SPP/IGP chipset. But as of press time, ironically enough, we couldn't find any AGP 8X-based motherboards that were actually shipping yet in the United States. Intel has also announced that it will launch two new chipsets with AGP 8X support before the end of this year.

Serial ATA
Today's parallel ATA interface--which connects internal hard disks and optical drives to a system's motherboard--has been around since the eighties and maxes out at 133MB per second. Early next year, a faster ATA interface will arrive that will quickly become the de facto drive interface for PCs. This new interface is called serial ATA and will first show up running at 150MB per second, but as the technology advances over time, it has the potential to transfer data as fast as 600MB per second.

Since serial ATA is a serial bus, the disk activity on one drive should have no significant effect on the performance of other disks on the same bus. And while you wouldn't want to yank out the disk that has your OS on it, serial ATA allows for hot-pluggable drives. Additionally, serial ATA cables use only 7 pins (vs. 40 pins for parallel ATA) and can be up to one meter in length (vs. 40cm for parallel ATA); this will permit thinner, longer, and more flexible cables, which should improve airflow inside computer cases and even facilitate smaller case designs.

Maxtor has already announced that it will start shipping serial ATA hard drives in December 2002. Numerous other manufacturers claim to have serial ATA controller cards ready to ship, most of which seem to be using chips from Marvell. In early 2003, expect to see serial-ATA-enabled motherboards using the Marvell controller, and even Intel just announced that it plans on building serial ATA into its chipsets.

PCI Express
When the PCI bus--the pathway between the CPU and peripherals such as network cards and sound cards--was first implemented in 1992, it was plenty fast. But with the extraordinary increase in CPU, memory, and peripheral speeds over the last decade, the PCI bus's poky data-transfer rate of 133MB per second has become the biggest bottleneck in today's desktops.

There have been some noticeable improvements to PCI technology recently, most notably PCI-X 1.0, which supports transfer rates of up to 1GB per second, but PCI-X has only recently gained a stronghold in expensive high-end workstations and servers. To further confuse matters, the PCI Special Interest Group has already approved two versions of a PCI-X 2.0 specification (PCI-X 266 and PCI 533) for 2003, with the faster version supporting speeds of up to 4.26GB per second.

But as the man said, "You ain't seen nothing yet!" While PCI-X is aimed firmly at the server market, an even faster bus called PCI Express (formerly know as 3GIO, or Third Generation I/O) is aimed squarely at the desktop segment for 2004. PCI Express is a hot-pluggable, serial I/ O interconnect bus (PCI and AGP are parallel buses) with a potential throughput of a whopping 8GB per second or even faster. PCI Express is designed to replace not only PCI and AGP slots but also some subsystem interconnections such as CPU, graphics, network, and disk I/ O. When PCI Express and commensurate expansion cards arrive on the scene, expect to see an immediate increase in performance of real-time 3D graphics rendering and network connections.

Get on the bus
It's a cliché, but technology indeed keeps marching on; and if we don't keep up with it, we'll be left in its wake. Your best bet is to get right on that bus when it comes by.