Power Consumption - 42 Watts When Idle At System Level

The new 780G northbridge

For reference - the northbridge of the 690G

Although the 780G northbridge (left) uses a smaller production process than the 690G northbridge (right), its die is larger, as it contains 133 million more transistors.

Even though the transistor count has almost tripled - growing from 72 million on the 690G to 205 million on the 780G - the northbridge heatsink is only slightly larger. This is possible because AMD has switched to a smaller production process, using 55 nm structures instead of 80 nm ones. This has allowed AMD to lower the power dissipation from 1.4 watts to 0.95 watts, while simultaneously integrating a more powerful graphics unit.

The flat cooler of the 780G northbridge.

Size comparison between the coolers of the 690G and 780G Northbridge chips.

This chart shows the development of transistor count and power consumption.

We compared the power consumption of the 780G board (Gigabyte GA-MA78GM-S2H) to that of a 690G board (Gigabyte GA-MA69GM-S2H) using identical hardware:

The Voltech PM3000A watt meter

All measurements were taken using a Voltech PM3000A power measuring device, with the processor idle and running at a reduced clock speed of 1000 MHz.

Although the transistor count of the Northbridge has increased from 72 million to 205 million, the 780G chipset draws about 2.37 watts less than its predecessor, the 690G. That translates to a 5.37% reduction in power consumption.

The wattmeter verified that the 780G-based system achieved a new power consumption record. Previously, only our own Solar Powered PC had been this frugal in the lab.