Power Consumption

For our power consumption readings, we run a Prime 95 load and slowly ramp up the number of threads in play, taking power data from the internal CPU registers that report for when turbo modes or thermal modes should activate. Depending on the CPU access, we can get data that varies from the full package down to individual cores, uncore, integrated graphics and DRAM controllers.

For the Ryzen CPUs, the API pulls out the total package power consumption first.

 Power: Total Package (Idle) Power: Total Package (1T)Power: Total Package (Full Load)

At idle, all the CPUs are pretty much equivalent. The cores are fully idle here, leaving the rest of the chip active enough for tick-over. As we ramp up the load, the higher-frequency Ryzen CPUs move towards their 65W TDP, with the Ryzen 3 1300X almost being spot on at 64.2W. The Intel CPUs are clocked higher, but only have two cores to contend with.  The Ryzen 3 1200 is clocked lower than the Ryzen 3 1300X, hitting a better efficiency point in the Zen design. This ultimately bodes well for upcoming quad-core SKUs in laptops.

Power: Cores Only (1T Load)Power: Cores Only (Full Load)

One of the odd things about the power consumption of the Ryzen 3 CPUs is the difference between how much power the cores internally measure compared to the full power consumption of the package measured as a whole, including the Infinity Fabric, DRAM controllers, IO and such. For the Ryzen 3 1200 for example, at full load the package has a power consumption of 40.43 W total, but the cores only count for 23.05W, leaving 17.38W on the table for the non-core elements in the chip. If we compare that to the Ryzen 5 1500X, we have 68.79W for the package and 49.69W for the cores, a 19.1W difference. For the Ryzen 7 1700X, it becomes 81.51W for the package and 62.10W for the cores, a 19.4W difference.

On the high-end chips, the difference is a smaller portion of the full power consumption, but on the Ryzen 3 processors the cores are only 57% of the power consumption, leaving 43% for the rest of the chip. A lot of this power could be the inter-CCX infinity fabric path, which means that packages like EPYC are giving away a lot of power to IF. If it is more other features, it could spell a number of problems for upcoming mobile chips, limiting the lower bounds of the power consumption. Naturally, I actually want to get my hands on to an EPYC processor in my own lab to see if we can pin down what is happening here.

Gaming Performance: Grand Theft Auto (1080p, 4K) Conclusion and Performance Per Dollar Graphs


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  • haukionkannel - Thursday, July 27, 2017 - link

    You can install Ryzen 1200 and use Nvidia 1080ti and run games at 4K easily, so there is a point of these prosessors.
    There will be Ryzen based APU later in this or next year for Office computers and maybe even htpc usage and laptops. Those Are budget CPU for gaming and you can pair them as fast GPU as you like and still get reasonable good results!
    The Intel 7700 is in the top, but if you run games at 4K I think that you can save a big deal by usin amd 1200 instead of Intel 7700! The difference is so small in speed and so big in money!
  • kaesden - Thursday, July 27, 2017 - link

    dont forget that ryzen 1200 with a 1080ti could also have a 1700 dropped in down the line when budget allows, or when more cpu performance is needed. And the ryzen based APU's are coming eventually for those who just want basic integrated graphics. AMD isn't finished yet with their roll out. Reply
  • zodiacfml - Thursday, July 27, 2017 - link

    The purpose is to make use/sell of disabled chips. This could be the reason why AMD and Nvidia started selling the new, lowest end discrete graphics cards. Desktop APUs will arrive early 2018.

    I wonder if AMD will ever have to cripple these Zen parts in the future as some articles mention they have high pretty good wields.
  • lefty2 - Thursday, July 27, 2017 - link

    They aren't "making" a $100 CPU with no iGPU, they are just re-badging a $500 CPU. Much cheaper in research costs than having to design a new die. ...and the same logic applies to the 7700K Reply
  • bennyg - Thursday, July 27, 2017 - link

    I think the price/perf discussion should be a it broader in scope than just comparing CPU alone. The need to find or buy a GPU for the R3 compared to the Intel competition is a noticable omisson. Even the budgestest secondhandest GPUs will throw out the metrics of a $30 price comparison, but the extra graphics performance and/or features you may get from a dedicated GPU over iGPU should also be considered. Reply
  • bennyg - Thursday, July 27, 2017 - link

    should be a *lot* broader. typo Reply
  • Manch - Friday, July 28, 2017 - link

    That's why these were tested with the higher end GPU's. To eliminate the IGP as a performance factor and compare CPU only. As you said, the extra performance you would get from even a low end discrete would be an unfair advantage for AMD. If you got one that was crappier than the IGP(if possible) then it would be an unfair advantage to Intel. It would be hard to decide which Discrete card would be the official stand in. On that note, doesn't AMD have discrete R7 cards that are paired with their APU's that are pretty much a copy of the IGP? They're not VEGA cores though so it wouldn't be a good way to predict the performance of the upcoming APU's. It would however give an idea as to what Bristol would have been using ZEN cores. Reply
  • extide - Saturday, July 29, 2017 - link

    Latest AMD APU's are still construction cores (Excavator) with Polaris based graphics. Ryzen with Vega based will come later. Reply
  • Alexvrb - Thursday, July 27, 2017 - link

    I don't know... maybe... gaming on a relatively small budget? Ryzen 3 plus a $150-200 graphics card is clearly better than an equivalent i3 build, plus they overclock even with a cheap B350 board. Reply
  • serendip - Friday, July 28, 2017 - link

    For a cheapo gamer like me, Ryzen 3 + a $100 card is fine, but how big is that market anyway?

    AMD needs to go beyond servicing enthusiasts, it has to get OEMs to use Ryzen in cheap PCs for basic use in schools, homes and businesses. These segments won't bother going for Ryzen 5 or i5, they just want the cheapest computer available. AMD doesn't have a good name in the low end of the market because of its terrible APUs.

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