Feeling the Heat

Computer makers are beginning to feel the heat, quite literally, as faster- and hotter-running microprocessors and compact computer designs are pushing the limits of what fan-based cooling systems can handle.

Within three to five years, researchers at Intel Corp., Hewlett-Packard Co. and IBM predict, computer makers will have to move beyond fans and adopt cooling systems such as radiators and micro-refrigerators within systems to avoid potential meltdowns.

"We dont have to look very far into the future to see where just putting a heat sink on a processor and blowing air over it is not going to work anymore," said Tomm Aldridge, director of enterprise architecture at Intel Labs, in Hillsboro, Ore.

Computer cooling will be among the hot topics at the Intel Developer Forum next week in San Jose, Calif., where several PC makers will discuss solutions to this looming industry problem.

Intel, the worlds largest PC and server chip maker, will tout manufacturing advances designed to produce more- energy-efficient processors. The Santa Clara, Calif., company will also promote a cooling technique that involves "growing" carbon nanotubes, which look like tiny patches of hair, on silicon surfaces.

"Carbon nanotubes have 10 to 100 times the thermal conductivity of metals," Aldridge said, and could make existing heat-sink-and-fan cooling systems more effective.

But even with those technologies, Intel said it expects its processors will begin to exceed existing thermal limits and, as a result, is also suggesting ways computer makers can redesign their systems to deal with hotter chips. One design Intel is pushing features liquid-filled tubes, like radiators, designed to draw away heat from processors.

While liquid-based solutions are a logical successor to air-cooled designs, Aldridge said, a number of issues need to be resolved before such solutions can be implemented.

"The challenges are finding a safe liquid solution that almost never leaks and, if it does leak, is not harmful to the computer," Aldridge said. "Then there are reliability issues. For example, are liquid pumps as reliable as ball-bearing fans? We dont know yet."