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How We Tested AMD's A10-7800

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

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:

Method
Contact-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
Equipment
1 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 System
MSI A88XM Socket FM2+
AMD Radeon Memory
Corsair H100i Closed-Loop Water Cooler
Corsair Neutron 480 GB SSD
SeaSonic X-Series PSU

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    Smallfilou , 19 August 2014 16:07
    Great product for a "family HTPC"! Fit it in a proper small enclosure and run it using a picoPSU or similar PSU. My bet is you can make it completely silent with proper cooling design (an without watercooling which in my opinion makes no sense at this point, be it in terms of power dissipation or price).