Samsung has announced GDDR4 memory chips that run at 4Gbps (4 gigabit per second, or 4GHz), two thirds faster than the current 2.4Gbps memory. It managed to make the higher speed chips by using 80 nanometer production technology. A nanometer is a millionth of a millimeter and the measurement refers to the size of the smallest feature on a chip's surface. As these sizes get smaller, chips can be made more compact, use less energy and work at higher speeds. Samsung's first 4G bps GDDR4 memory will be a 512M bit (64M byte) chip. The South Korean company will begin offering sample chips to customers this month and mass production will come later this.

The experimental 512Mb GDDR4 memory chips from Samsung were produced using 80nm process technology and were designed for power supply voltage of 1.4V - 2.1V, reports PC Watch web-site. The data rate of 4Gb/s (4 gigabit per second, or 4GHz) was achieved with devices operating at 2.0V, which is higher than Samsung's current-generation GDDR4 chips that can function at up to 1.9V officially.

GDDR4 memory at 4.0GHz delivers bandwidth of 16GB/s and if such chips were used in today's graphics cards that have 256-bit memory bus, this would result in peak data bandwidth of 128GB/s, two times more than the ATI Radeon X1950 XTX (the only graphics card on the market that uses GDDR4) can offer. For tomorrow's graphics boards that will have 512-bit memory access Samsung's new chips would give peak memory bandwidth of 256GB/s, which is nearly three times more than 86.4GB/s that the currently highest-performance graphics card - Nvidia GeForce 8800 GTX - has.

Originally it was estimated that GDDR4 would scale to about 2.8GHz in 2007 and in 2008 the GDDR5 would kick off at 3.5GHz to reach 4GHz speeds in 2009. However, Samsung's new chips may cause the industry to revise technology roadmap, especially keeping in mind that Samsung has been able to clock the GDDR4 at 3.20GHz about a year ago.