I joined MDR seven years ago to cover PC platform technology, an
area that has experienced tremendous progress over the years. In
just the past three years, we've seen front-side bus speeds—a
critical constraint for processor performance—soar from the
133MHz of Intel's Pentium III to the 800MHz of the new Pentium 4.
That's a 6:1 improvement, better than Moore's Law would predict.
Memory bandwidth has increased comparably, with single banks of
133MHz SDRAM giving way to the dual banks of DDR400 SDRAM in today's
best desktop PCs.
Software development used to lead hardware development: each new
version of Windows and each new major application, such as DVD playback,
used to arrive before PCs were fast enough to take full advantage
of them. Today, the situation is reversed. Even low-cost PCs are
more than fast enough for the software they're likely to run. Only
in a few niche markets, such as 3D games, are PCs strained to their
limits.
Peripherals have also lagged behind. The ATA hard-disk interface
is just twice as fast today than it was three years ago. The hard
disks themselves are improving at a similar rate, but they continue
to be a limiting factor for many kinds of software. The 100Mb/s
Fast Ethernet standard still accounts for almost all local-area
networks; Gigabit Ethernet has been slow to catch on.
During the next year, we'll see several new technologies arrive
on our desktops that will help break these performance logjams and
open the market to new applications. The Serial ATA standard, for
example, will support a 150MB/s transfer rate, and this rate will
double again within two years. Serial ATA will make it easier for
end users to add another drive to their systems, and, with disk-array
technology, such an upgrade can boost performance as well as capacity.
PCI Express will remove another obstacle to end-user system expansion
by providing more than enough bandwidth for tomorrow's high-performance
peripherals. The familiar PCI bus isn't even fast enough for many
of today's needs, so PCI Express is long overdue.
I/O coprocessing isn't a new technology, but it's one we're likely
to see more of in mainstream systems. Graphics cards are coprocessors
already, doing tasks that were once the responsibility of the CPU.
I believe networking will be the next major role for coprocessors
in the PC. Running the TCP/IP stack for a Gigabit Ethernet link
can consume the equivalent of a 2GHz processor—or a $20 ASIC.
That's a pretty easy choice to make. On the other hand, high-definition
video processing is only a temporary market for coprocessors. The
HDTV standard will be with us for many years, and CPUs will soon
be fast enough to handle HDTV for most users.
The transition to 64-bit desktops, however it takes place, will
impose new requirements on the PC platform. With 4G of DRAM available
at retail for less than $500, and with further price cuts inevitable,
we need to have PC motherboards with more memory slots than the
two or three that have become commonplace—at least at the high
end of the market. Similarly, now that multithreaded operating systems
and applications are commonplace, we should see a return to dual-processor
configurations for high-end desktops.
PC buyers have always responded well to technology transitions
that promise dramatic improvements in system capabilities, and software
developers have always come through with new ways to take advantage
of these capabilities. Today's PCs are more than a match for yesterday's
supercomputers. What will tomorrow's PCs be like?
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