A research team has managed to build a computer chip that it claims is 15 times more efficient than current chips — and all it has to do is make a few mistakes. The so-called "inexact" chip allows its processing components to make the occasional error, which researchers have found both cuts down energy use and boosts performance. The design of the chip uses a technique called pruning, which removes some of its rarely used components, and has the added benefit of making the chip even smaller. The concept has been in development since 2003, but now the team has built an actual working prototype.

"I am delighted that these working chips have met and even exceeded our expectations," project leader Krishna Palem said. The research was a joint effort between Rice University and the University of California, Berkeley in the US, Singapore's Nanyang Technological University, and the Center for Electronics and Microtechnology in Switzerland. And while a chip that makes mistakes may not sound too appealing, the team says that certain applications are able to "tolerate quite a bit of error." Image processing, for instance, can have an error rate as high as 7.5 percent due to the human eye's ability to correct errors. Though as you can see from the image below, images processed using inexact chips do leave something to be desired (the image on the far right has a relative error of 7.58 percent).

The chips are expected to be used in prototype hearing aids and I-slate tablets designed for students in India by 2013.