DDR-2 or DDR-3: When Speed Is Not Enough

From EDO RAM to SDRAM to DDR to DDR-2, there is no looking back for memory
technologies. And before the masses could experience the current DDR2, the DDR3
will arrive. This may make DDR2 a short-lived success.

Technological advancement is all about speed and size. Be it computers or any
other technology, it is a never-ending race, where the motto is 'faster and
smaller'. Moore's law is quite a popular one in the world of computing
technology, which says that the number of transistors on a processor doubles
every 18 months making it twice faster.

Over the years, computer memory technology has also evolved just like the
processor. Few years ago, the launch of Pentium-II popularized the SDRAM memory
market. Then came the DDR (Double Data Rate) memory predominantly designed to
support the Pentium-4 platform.

However, the transition from SDRAM to DDR was not immediate. For very long,
manufacturers produced a motherboard that could support both SDRAM and DDR on
the P4 platform. And over a period of time, SDRAM was out from the P4
motherboards.

As this happened, another memory technology was taking shape-the DDR2. The
DDR2 transfers 64 bits of data twice every clock cycle for an effective transfer
rate twice that of the FSB of a computer system, and an effective bandwidth
equal to its speed x 8. In simple terms this means, the DDR2 is supposed to be
twice faster than the DDR in terms of the fetch rate.

The DDR2 memory is not compatible with current DDR slots as it uses a new
240-pin form factor instead of 184, and hence is not backward compatible.

DDR2
also implements on-die termination, a memory modification that delivers electric
improvements to memory modules. Using on-die termination, memory bus resistors
are placed inside the chips rather than on the motherboard, which was how
previous generations of memory handled electric noise. When the chip is working,
the resistors are deactivated, and when the chip is in an idle standby state,
the resistors are activated.

However, the current DDR, which operates at a maximum frequency of 400 Mhz is
as fast as the DDR2 memory operation at 533MHz. With no or very little
performance gain, this is obviously not a good choice for customers. However,
what should be noted is that the benefits come in the form of less needed power
to perform processes. DDR2 uses 1.8v of power, as opposed to DDR's 2.5v,
making this memory module less power-hungry and will operate at cooler
temperature.

DDR2 starts where DDR stop

Further development on the DDR ended at 400 MHz, while DDR2 starts at 400
MHz and touches 800 MHz. That is not the limit, some makers of expensive memory
modules have already released DDR2 products capable of working at 933MHz-1066MHz
frequencies, but those are designed for overclockers and enthusiasts, who run
PCs on the limit.

Elpida and Samsung Electronics commenced testing the DDR2 in mid-2002, nearly
two years before commercial launch. Infineon began to sample DDR2 in March,
2003, about 16 months before the first actual platforms supporting the memory
type — Intel's 915P/G and 925X chipsets — were introduced commercially.
Today, nearly a year after it was first commercially launched in mid-2004, DDR2
is waiting to become popular.

There still isn't that much market demand for DDR2 modules because it is
not just technology that drives the Indian market, but the price, which plays a
big role in the popularity of any technology product. The current
price/performance ratio of DDR2 is just too high for most users to migrate from
DDR systems. An entry level DDR2 533MHz module is still costlier by Rs 500 to Rs
800.

Another reason for the DDR2 not becoming popular is the supporting platforms.
The Intel 845, 865 and 875 chipset-based motherboards are still very popular,
which uses the DDR memory. Currently, the DDR2 is available only for the 915 and
925 chipset-based motherboards here in India.

915 and 925 chipset-based motherboards have picked up lately worldwide and is
expected to gain popularity in the Indian market as well. This will surely bring
down the price gap between DDR and DDR2 in the next few months. In fact, spot
DDR2 pricing plummeted to levels below the DDR memory cost, according to
Taiwanese largest memory exchange. This is likely to cause DDR2 memory modules
quotes to get lower than pricing of modules based on DDR memory in a few weeks
time, which may boost popularity of computer platforms designed for DDR2.

 Lower pricing of DDR2 memory may accelerate sales of platforms that
support DDR2 SDRAM only, such as Intel 945- and 955-series chipset based as well
as NVIDIA nForce4 Intel edition-based motherboard. This may boost sales of Intel
Pentium and Celeron D-series processors in LGA775 package, as modern platforms
do not support Socket 478.

Several global manufacturers of memory have also transited some of their
production from DDR chips to DDR2 and NAND flash production. There's no doubt
that if you are considering building a system today for extreme gaming or
high-end graphics applications, DDR2 is an option worth considering. As more and
more motherboard manufacturers start pushing the technology along, it is sure to
gain momentum among performance enthusiasts.

DDR3 in the queue

By the time the price drop reflects on the Indian market, consumers will be
in for another surprise, i.e. - DDR3 and XDR.

DDR3 and XDR are expected to be mass-produced in the second half of 2006 or
even in the second half of 2007 respectively.

Infineon, the Munich, Germany-based memory supplier will have DDR3 available
for customers to sample around the end of 2006, the company's execs recently
said. Theoretically this may indicate that commercial DDR3 production may begin
about a year after, in late 2007.

Intel Corp.'s plans included platforms supporting DDR3 memory in 2007,
which is likely to catalyze memory makers to arrange commercial manufacturing of
DDR3 SDRAM in 2007. Still, some makers may offer DDR3 for non-PC applications,
such as networking devices, earlier than Intel proposes a desktop platform with
DDR3 support.

Samsung Electronics announced in mid-February it had made the world's first
512Mb memory chip which complies to next-generation DDR3 standard and can
operate at the speed on 1066MHz. The prototype operates at 1.5V and transfers
data at the speed of 1066Mbps. Samsung says DDR3 memory will be made using 80nm
process technology; at present the company uses 90nm for DDR and DDR2 SDRAM
production.

Samsung quoted market research firm IDC as saying that the first DDR3 DRAMs
will be sold in 2006 and that the DDR3 will represent 65% of the entire DRAM
market in 2009.

For DDR III, JEDEC* intends to follow the same development model that was
used so successfully in the past with SDRAM, DDR and DDR2. By including input
from all the major OEMs, DRAM suppliers, Connector companies, Chipset vendors,
Testing companies and Support companies JEDEC will ensure that DDR3 becomes the
next DRAM standard

* (JEDEC, the leading developer of standards for the solid-state industry, is
a sector of the Electronic Industries Alliance (EIA). EIA is the trade
association that represents manufacturers in all areas of electronics.) 

NELSON JOHNY