AMD Ryzen 7 1800X CPU Review

AMD SenseMI Suite & XFR

AMD's SenseMI feature suite consists of five key technologies that allow Ryzen 7 processors to adjust performance and power consumption parameters in real time.

Pure Power

According to AMD, its Zen architecture employs an array of 1000 sensors accurate to 1mA, 1mV, and 1°C. The Pure Power feature monitors these temperatures, voltages, and currents, enabling real-time adjustments based on decisions made by what company representatives describe as learning algorithms.

Those sensors feed telemetry data across the Infinity Fabric loop to the Infinity System Management Unit at 1ms intervals. The management unit analyzes that data and issues commands across the fabric to adjust voltage and frequency settings for optimal performance. AMD also notes this functionality helps manage its speculative cache features and AI-based branch prediction.

Each piece of silicon is unique, and AMD points out that its algorithms allow the processor to optimize itself based upon its own characteristics. Notably, other semiconductor vendors employ a similar technique to control the power consumption of their processors dynamically.

Precision Boost

Precision Boost adjusts the power/performance curve to optimal settings for the operating environment, much like Intel's Turbo Boost, based on information derived from Pure Power. The algorithms that control Precision Boost facilitate changes in 25 MHz steps, which is of course more granular than Turbo Boost's 100 MHz increments.

On the Ryzen 7 1800X, for example, Precision Boost increases the 3.6 GHz base frequency to 3.7 GHz across all cores, and can push two cores up to 4 GHz. This is important: whereas Intel's Turbo Boost technology varies clock rate based on the number of active cores, Precision Boost draws that distinction between two active cores and anything in excess of two cores, at which point maximum frequency drops to the all-cores number. What you end up with is a nice speed-up in lightly-threaded tasks, but less benefit than Turbo Boost as soon as a third core spins up.

XFR (eXtended Frequency Range)

AMD's eXtended Frequency Range feature allows the processor to dynamically adjust its clock rate above the stock and Precision Boost clocks based on available thermal headroom.

XFR automatically increases the Ryzen 7 1800X's Precision Boost ceiling by 100 MHz if your cooling solution can keep the CPU running below a certain threshold. We tested with Noctua's NH-U112S SE-AM4 air cooler and Corsair's H100i v2 closed-loop liquid cooler, and both perform well enough to engage XFR, allowing a 4.1 GHz peak clock rate. Unfortunately, we don't have AMD's stock heat sink/fan, so we don't know if it's beefy enough to make XFR work.

AMD claims this feature scales with air, water, and LN2 cooling, but doesn't specify if there's a maximum frequency with LN2.

Interestingly, the Precision Boost and XFR features are intertwined on our Asus Crosshair VI Hero motherboard. If you enable the "Core Performance Boost" setting, the 1800X triggers both Precision Boost and XFR frequencies based on your workload. But you cannot disable either feature independent of the other.

Neural Net Prediction & Smart Prefetch

AMD claims that its Neural Net Prediction capability describes a built-in neural network able to learn application behavior and pre-load instructions before they're needed, while Smart Prefetch learns access patterns to pre-load data into local cache.

Both features appear to be marketing-speak for AMD's perceptron branch predictor, which debuted in the Jaguar core. Of course, the company likely improved and optimized this technology for Zen, specifically, but it's not magic.

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    Top Comments
  • Pompompaihn
    All along AMD was claiming to equal/beat Broadwell-E in comparative tasks at half the price, and from another review that included Broadwell-E, it's done that. I don't recall ANY AMD press saying it was going to beat the 7700K in straight up gaming. So, target set, and hit. That's a win in my book. But now, need to see what they can do with the smaller core count chips and if they can scale frequency to be competitive in the gaming sector.
    57
  • vrumor
    Well, at the very least, it is competition. Competition drives innovation and lower costs. Well done AMD.
    47
  • Pompompaihn
    @cabose369

    Their slides showed it beating it in Cinebench, in which it absolutely crushes the 6900k. Ask Intel why they don't have any gaming 8 core chips. This is a productivity chip that is GOOD at gaming and will be BETTER at gaming as more multi-threaded games are released and DirectX12 is implemented. There's no single chip on the market that's best at everything, Ryzen eats the quad core I7s for lunch in rendering, and the faster lower core count i7s beat Ryzen in most gaming. They also beat Broadwell-E in gaming. I think you're missing reality here.
    39
  • Other Comments
  • vrumor
    Well, at the very least, it is competition. Competition drives innovation and lower costs. Well done AMD.
    47
  • kiniku
    Why did I feel AMD was hiding something? Understandably the "gamer market" is comparatively small. But couldn't AMD have designed a CPU that worked well in gaming/desktops and in data centers? Disappointing.
    (But I have a 5820K. The best Ryzen in the world would not have had me switch anyway.)
    -16
  • xryanx123
    Bias review as always. Most of your information is obviously screwed up. How do you get 4.0ghz at 1.45v. When that's not even an overclock for the chip (not really at least compared to stock) yet you're already pushing 1.45v? You're tailoring your articles for the uneducated. Duck off toms
    -23
  • captaincharisma
    in the end the best anyone can hope from AMD is that it spooked intel enough to lower its prices
    -6
  • ssdpro
    In a hurry to compare various site's gaming results, it appears differing sites are finding the same thing: gaming performance is acceptable but below 4c/8t Intel offerings. If you spend your day encoding or multi-thread benching this is a monster bargain.

    With the good and bad, I think we can all agree the good here is competition. There is some now.
    30
  • Pompompaihn
    All along AMD was claiming to equal/beat Broadwell-E in comparative tasks at half the price, and from another review that included Broadwell-E, it's done that. I don't recall ANY AMD press saying it was going to beat the 7700K in straight up gaming. So, target set, and hit. That's a win in my book. But now, need to see what they can do with the smaller core count chips and if they can scale frequency to be competitive in the gaming sector.
    57
  • Dionisiatis
    Maybe i missed it but i would love to see a perf/dollar ratio comparison. Im sure Ryzen would occupy the top position, and it would also make it clear that AMD achieved extraordinary results in bringing such high performance to the average consumer that cant 700+ dollars for a CPU.
    20
  • jackspeed
    @Dionisiatis the 7700K is cheaper then the 1800X so for gamers it currently is the best CPU. now games have yet to optimize for the new AMD architecture, so maybe soon it will be a different story.
    14
  • Aspiring techie
    Your "Heating up AMD Ryzen" video on the Power and Temperatures tab is still private. I can't watch it.
    3
  • freak777power
    Fails in gaming, and for multitasking stuff i got Xeon 14/28 who is doing all that encoding and other stuff for $300 on eBay.

    In my opinion AMD failed and they really pulled BS by fooling people into pre ordering but it turns out that in gaming sucks..
    -24
  • cabose369
    Well, well, well... What a surprise.... AMD makes tons of grandiose claims (such as it will beat the i7-6900K), and then can't back it up. Same old AMD. Just wait for when they hype up Vega and it ends up not being able to beat NVIDIA. Oh dear AMD.
    -25
  • cabose369
    @Pompompaihn They claimed the 1700 (not X model) would easily defeat the Core I7-7700K in their slides from last week. It's kind of bad though when their top model (1800K) can't even beat the 7700K...
    -23
  • thegentlewoman
    Lower "its" prices .. yes indeed INTEL MAKES ITS PRICES. I will never buy such technology (of Intel) it's dirty of blood not just of monopoly, but it's deeply unethic, just like Apple after the death of its Human Guide. Now I say thanks to AMD, and keep up... we want a Multiple players competition not just polarization (masses love it) and duopoles.
    Thanks again!
    4
  • bnolsen
    So how are these compiled? Our HTPC application needs to run on lots of systems so we pretty much have support for i7 nehalem as our compile target as customers have sandy, ivy, haswell based xeon systems. Might be a 40core amd around there somewhere too. So mostly SSE2 and 64bit. AVX, etc aren't even on our radar.
    1
  • SteelCity1981
    im not surprised by the gaming results. the vast majority of modern games dont take advantage of more than 4 cores right now so a fast clocked quad core will beat out a slower clocked hexa or octo core every time.
    14
  • Brian_R170
    AMD did a good job at matching Broadwell-E, and that's obviously why all of the leaks and official marketing showed those comparisons, but what is disappointing is that AMD continually stated that their intentions to supporting the gaming community and I expected a no-excuses gaming chip out of the gate. I guess we'll have to wait and see what the quad-core offerings are like.
    2
  • wh3resmycar
    damn. at the end of the ryzen presentation, Lisa Su said that she was confident the 1800x IS THE FASTED 8c/16t chip out there and we have this? man oh man oh man.
    -7
  • cloudonsky
    AMD didn't optimize HEVC encoding. THG review is incomplete once again
    -9
  • chaosmassive
    Dear Tom's Hardware Mods/Admin/Programmer

    please fix your images on your pages, I cant see anything beside of your wall of texts

    Regards,

    Lowly Reader
    2
  • Pompompaihn
    @cabose369

    Their slides showed it beating it in Cinebench, in which it absolutely crushes the 6900k. Ask Intel why they don't have any gaming 8 core chips. This is a productivity chip that is GOOD at gaming and will be BETTER at gaming as more multi-threaded games are released and DirectX12 is implemented. There's no single chip on the market that's best at everything, Ryzen eats the quad core I7s for lunch in rendering, and the faster lower core count i7s beat Ryzen in most gaming. They also beat Broadwell-E in gaming. I think you're missing reality here.
    39