Skip to main content

AMD A10-7800 APU Review: Kaveri Hits the Efficiency Sweet Spot

How We Tested AMD's A10-7800

While we adapted our graphics card test setup for the APU tests, the equipment didn't change. The HAMEG HZO 3054 (Rohde & Schwarz) is the core instrument, a fast four-channel DSO that can be remote-controlled via Ethernet and store up to 60,000 samples per channel.

We run the 12 V wires of the eight-pin (2 x four-pin) CPU power cable through a current probe, as shown in the left picture below, and also the 24-pin cable's 12 V wires (on the right). That makes four HAMEG HZO50 probes to measure the current without having to insert a series resistor into any cable. Simultaneously, each rail’s voltage is fed into a HAMEG HMC8012, which also has the deep storage and remote control options installed.

Image 1 of 2

Image 2 of 2

In order to tame the massive amount of data, we use a custom program and Excel. A measurement takes a full minute, and the sampling interval is 10 ms, which results in 6000 samples. Shrinking the sampling interval further wouldn't yield a tangible benefit, and would instead drown us in test data.

Unsurprisingly, at less than 100 W power draw, platform-oriented benchmarking isn't as wild as some of the graphics card-based results we've seen, and the motherboard doesn’t impose massive load spikes on the PSU. But there are still a few noteworthy observations.

As a preview to the following pages, let’s look at the motherboard's power draw in one second:

Test Setup and Test Equipment:

MethodContact-free DC measurement at PCIe slot (using a riser card) Contact-free DC measurement at external auxiliary power supply cable Mass-free Voltage measurement at external auxiliary power supply cable
Equipment1 x HAMEG HMO 3054, 500 MHz digital multi-channel oscilloscope 4 x HAMEG HZO50 current probes 3 x HAMEG HZ355 (10:1 probes, 500 MHz) 1 x HAMEG HMC 8012 digital multimeter with real-time storage function
Test SystemMSI A88XM Socket FM2+ AMD Radeon Memory Corsair H100i Closed-Loop Water Cooler Corsair Neutron 480 GB SSD SeaSonic X-Series PSU