AMD Kaveri Review: A10-7850K, A10-7700K and A8-7600

Power Consumption and Thermals

AMD claimed to have knocked 5W off the TDP of the Kaveri flagship versus Richland going from 100W to 95W. In practice we saw as much as a 25W reduction when comparing equivalent parts. At the lower end Kaveri’s A8-7600 45W part did perform drastically better than the A8-6500T and now we can see where a lot of that performance came from – the A8-7600 consumes almost 13W (17%) more despite having the same 45W TDP so it is hardly a fair comparison. However, even so the A8-7600 is still an incredibly efficient part consuming less than both Haswell units but offering very compelling performance in GPU-centric applications such as gaming and photo work. Both of Intel’s parts showed exceptional efficiency, especially at idle, thanks to the incredibly power frugal nature of the Haswell design and the advanced idle sleep states.

Looking at those power figures in more detail and we can see where the power savings have been made. GPU power consumption is largely identical across the whole Kaveri and Richland Range excluding the A8-6500T. The big power savings with Kaveri have come from the CPU side thanks to Steamroller’s higher IPC allowing for a lower overall clock speed which has reduced power consumption a lot. Despite the improvements Intel still dominate in the realm of CPU power efficiency as they consume significantly less than all the Kaveri parts, and most the Richland parts, yet are still offering significantly more CPU performance.

In terms of temperatures with Kaveri it isn’t possible to judge. The temperature readouts on the Kaveri APUs are totally “borked” and the motherboard sensor readouts give ridiculously low temperatures which cannot be accurate – 37 degrees at full load for the A10-7850K? I think not. We did also note down AMD’s alternative temperature measurement, known as the “thermal margin”, but AMD told us these cannot be converted into actual temperatures. You can see those thermal margins below. The thermal margin indicates the thermal distance from the threshold at which thermal throttling occurs. The higher the number the lower the temperature because the further it is away from the thermal limit.

• AMD A10-7800K. 70 Degrees thermal margin to thermal threshold at idle, 57.9 Degrees thermal margin to thermal threshold at load
• AMD A10-7700K. 70 idle, 58.2 load.
• AMD A8-7600 (65W). 70 idle, 58.8 load.
• AMD A8-7600 (45W). 70 idle, 65.8 load.

The overall pattern in terms of temperatures then isn’t really possible to judge but we think the Kaveri APUs will be running at similar temperatures to Richland or possibly slightly lower. Temperature increases are likely to result from a more dense die with a larger GPU part but at the same time the reduced overall thermal output from a more efficient CPU probably counteracts that.