Raspberry Pi gets "turbo mode"

The makers of the DIY computer the Raspberry Pi have decided to add a turbo mode to the computer so that it can run at a blistering 1Ghz.

According to its site, Raspberry Pi has supported overclicking and overvolting since the launch.

By editing config.txt overvolting provided more overclocking headroom, but voided the warranty.

In fact the Raspberry people even set a sticky bit inside BCM2835 to allow for spotting boards which have been overvolted.

But since the launch the Raspberry team’s engineers have done a lot of work to understand the impact of voltage and temperature on lifetime. They have come up with a “turbo mode”, which dynamically enables overclock and overvolt under the control of a cpufreq driver, without affecting the warranty.

The chip only applies the turbo when it is busy, and limits its activity when the BCM2835′s internal temperature reaches 85°C.

This means that there is no measurable reduction in the lifetime of a Raspberry Pi.

The company said that users can choose from one of five overclock presets in raspi-config, the highest of which runs the ARM at 1GHz.

If you have the 1GHz turbo enabled, against the previous image at 700MHz, nbench reports 52 percent faster on integer, 64 percent faster on floating point and 55 percent faster on memory.