Power Draw: Overview
We collect tons of data from each test run, which we then analyze in different ways. Today, we're going to present the power measurements at idle, under a gaming load, and under the most stress possible. Then, we'll dig into more specific details. The APU's power consumption is measured at the eight-pin 12 V connector. Simultaneously, we get the motherboard and memory draw at the 24-pin ATX connector. Total consumption is the sum of all power rails leading to the motherboard, without the SSD.
AMD promised us an efficiency surprise and, spoiler alert, it delivers. What does that achievement look like in detail, though?
Power Draw at Idle
MSI's motherboard and AMD's APU form an exciting low-power team. At a mere 6.4 W for the APU and 11.7 W for the total system, the platform's draw is impressively low.
While the 19 W measured at the wall socket is quite low as well, PSUs with an 80 PLUS Gold rating fail to hit our efficiency expectations at such a low power draw, even if they still technically comply with the specification. Plug in a DC-DC converter (which we can no longer call a picoPSU for legal reasons) and an efficient wall wart-style PSU; you can achieve less than 15 W at the outlet.
Power Draw Idle | Minimum | Maximum | Average |
---|---|---|---|
CPU +12 V | 4.8 W | 24.0 W | 6.4 W |
Motherboard +12 V | 0.0 W | 14.4 W | 4.8 W |
Motherboard +3.3 V | 0.0 W | 0.1 W | 0.0 W |
Motherboard +5 V | 0.1 W | 1.1 W | 0.4 W |
System Total | 4.9 W | 38.9 W | 11.7 W |
Power Draw during Gaming
The next efficiency surprise is already waiting for us in the gaming benchmarks. While the A10-7800-based system is just a bit slower than one built using an A10-7850K, its power draw is quite a bit lower (32 W for the APU on average, and 40.3 W for the whole system). Similar to graphics cards, we observe peaks under load as high as 55 W. But the average proves that AMD operates the A10-7800 closer to its architecture's sweet spot. We used Unigine Heaven 4.0 at moderate quality settings to max out the APU, finding the results to be easily reproducible.
Power Draw Gaming | Minimum | Maximum | Average |
---|---|---|---|
CPU +12 V | 7.2 W | 55.2 W | 32.0 W |
Motherboard +12 V | 0.0 W | 24.0 W | 7.1 W |
Motherboard +3.3 V | 0.0 W | 0.1 W | 0.1 W |
Motherboard +5 V | 0.3 W | 1.9 W | 1.1 W |
System Total | 12.8 W | 70.8 W | 40.3 W |
Power Draw at Full Load
Even at full load, the test system doesn’t exceed AMD's 65 W TDP unless you increase voltage for an overclock. We briefly played around with these motherboard settings, but found that the system took a huge efficiency hit, while performance barely increased. Hence, we went back to the default values and enjoyed an easy-to-cool machine with decent performance.
Power Draw (Full Load) | Minimum | Maximum | Average |
---|---|---|---|
CPU +12 V | 7.2 W | 88.8 W | 56.2 W |
Motherboard +12 V | 0.0 W | 19.2 W | 6.5 W |
Motherboard +3.3 V | 0.0 W | 0.1 W | 0.1 W |
Motherboard +5 V | 0.1 W | 1.7 W | 0.8 W |
System Total | 13.0 W | 95.0 W | 63.6 W |