A super-cooled computer chip has shattered speed records for silicon-based electronics - but don't expect your PC to hum along at 500 gigahertz anytime soon.

The chip only ran at the high speed when it was cooled to 451 degrees below zero - just eight degrees above absolute zero, the coldest temperature possible in nature, researchers at IBM Corp and Georgia Tech said.

Still, researchers believe they can improve the technology so that high speeds can be reached at room temperature; a development that could lead to advances in cell phones, radar technology and space exploration, among other applications.

The typical mobile phone chip today runs at 2 GHz, while the highest-end PC microprocessors run at less than 4 GHz.

"The industry always wants more," said John Cressler, a professor with Georgia Tech's School of Electrical and Computer Engineering.

"People are always wondering how far silicon can take us, and this should show there's a lot of mileage left to go."

Prof Cressler and a team of 22 scientists and graduate students forged the chip by melding silicon with atoms of the element germanium, a process so fragile that even the tiniest miscue could evaporate their work.

It took researchers nine months to invent a new process to clock the chip by injecting liquid helium into a probing station.

Scientists can view the process through a powerful electronic microscope zoomed to see the tiny chip, only a few thousandths of a millimetre wide.

Silicon remains the cheapest and easiest material to mass produce, and researchers say this latest development is an important step in showing the electronics industry the speeds that silicon-based chips could reach.

The previous speed for a silicon-based chip, set at room temperature, was 375 GHz. While the Georgia Tech team's chip set a slightly lower speed at the same temperature - about 350 GHz - Prof Cressler said there is plenty of room to improve.

"This is a first look at what the limits can be," he said.

"I'm hoping this record can be broken a few times."