NZXT’s Kraken X72 closed-loop liquid cooler is another in the XX2 series, following the 280mm X62 that we previously reviewed. The X72 is a 360mm cooler, putting it in more direct competition with the Corsair H150i Pro (the first to feature a 6th-gen pump) and Fractal S36, and indirect competition – in performance only – with the EVGA CLC 280.
NZXT’s X72 costs $200, making it one of the most expensive CLCs on the market. The Floe 360 lands at around $184, the EK Phoenix 360 – a semi-open solution – is the only one that lands significantly higher. The X72 still uses the same pump design as when we tore-down the X42, running Asetek’s 5th Gen pump and a custom, NZXT-designed PCB for RGB lighting effects. Functionally, 5th Gen has proven to be marginally superior – technically – to its 6th Gen for outright cooling performance. We’re talking nearly margins of error. The newest generation is presently only used on Corsair’s H150i and H115i Pro products, as Corsair largely dictated what went into the 6th generation. Major differences are made-up by the metal impeller, similar to the one used by Dynatron in old Antec Kuhler products, rather than a 3-prong plastic impeller. These don’t perform differently in terms of thermals, but there should be reduced susceptibility to heated liquid, and theoretically reduced hotspots as a result of the new 6th Generation design. That doesn’t manifest in outright performance, but might manifest in endurance. We won’t know for a few years, realistically.
Our primary tests for the NZXT Kraken X72 review and benchmark include the following:
- 100% fan / 100% pump
- 100% fan / silent pump
- 63% fan (40dBA)
We’ve previously tested custom copper integrated heat spreaders (IHS) for Intel, primarily the unit sold by Rockit Cool for LGA115X CPUs. Our findings of the custom copper IHS (sold here) for the i7-8700K were that, generally, it was a fun, worthwhile project at $20, but that the thermal improvement was not game-changing. It was still impressive, though, as we monitored between 4-5 degrees Celsius improvement from the IHS replacement on the 8700K, partly benefiting as a result of the increased surface area over the stock Intel heat spreader. That’s a lot of uplift for something that isn’t a CPU cooler, and if you’re up against hard requirements for noise in your system, it could allow for just enough headroom to slow-down the case fans a bit more.
Ryzen is different, as its heatspreader is one large block, as opposed to a machined block with cut-outs and dips and generally smaller surface area. Rockit Cool improved on Intel IHS performance by increasing surface area, but had little to improve on with AMD’s. Both Intel and AMD use copper IHS units, but all of them are nickel-plated. This shouldn’t impact performance significantly and helps with cleaning.
Today, we’re benchmarking a custom copper IHS for AMD Ryzen CPUs and APUs, using the Rockit Cool copper IHS on an AMD R3 2200G that we previously delidded and benchmarked.
The headlining story for the past week covers the memory supplier class action that was recently filed (vs. SK Hynix, Samsung, and Micron), alleging conspiracy to fix prices. In contension for the headline story, Intel's 10nm process problems have grown more complicated, seemingly preempting the company's hiring of Jim Keller, former AMD Zen architect.
Our Ask GN series was put on hold during the onslaught of Ryzen 2, Hades Canyon, and X470 coverage of late. We're back in force, though, with two back-to-back episodes. The second will go live tomorrow, the first tonight. For this week's episode, we're talking B450 motherboard expectations (and Computex), realistic ways the GPU market might make a comeback, review sampling, HPET benchmarks, and more.
Separately, please note that we are planning a livestream for 5/1 at 7PM EST. The stream will be hosted on our YouTube channel. We will be attempting to overclock Hades Canyon further than our current record of 4.7GHz. We're hoping to push closer to 5GHz, but power may become a limitation at some point. We've already posted preliminary results over here. Be sure to tune in for the livestream! It'll be a fun one.
Both Amazon and Newegg both have some noteworthy sales tonight (and some for only tonight), for anyone planning upgrades amidst the current great DIY PC crisis (see: RAM and GPU prices). The best deals include a couple of motherboards and AMD’s Threadripper 1950X. The deals appear to be good for the next 8 hours, at the time of this writing.
Some controversy bubbled-up recently when reddit, as it does, found its newest offense at which it could express collective rage. That offense was AMD’s CPU warranty, which had previously indicated that any cooler aside from included stock coolers would violate the warranty – not that they’d be able to prove it, if we’re being honest.
We reached-out to AMD for comment when this story went public, and received a response today that AMD had updated its warranty terms for clarity. The original language was meant to prevent warranty replacements for scenarios where the CPU had been damaged by an out-of-spec cooler (think: something like an LN2 pot, or the jury-rigging we do at GN). It was not meant to block warranty replacements for issues unrelated to coolers.
For our 2700/2700X review, we wanted to see how Ryzen 2’s volt-frequency performance compared to Ryzen 1. We took our Ryzen 7 2700X and an R7 1700 and clocked them both to 4GHz, and then found the lowest possible voltage that would allow them to survive stress tests in Blender and Prime95. Full results are included in that review, but the most important point was this: the 1700 needed at least 1.425v to maintain stability, while the 2700X required only 1.162v (value reported by HWiNFO, not what was set in BIOS).
This drew our attention, because we already knew that our 2700X could barely manage 4.2GHz at >1.425v. In other words, a 5% increase in frequency from 4 to 4.2GHz required a 22.6% increase in reported voltage.
Frequency in Ryzen 2 has started to behave like GPU Boost 3.0, where temperature, power consumption, and voltage heavily impact boosting behavior when left unmanaged. Our initial experience with Ryzen 2 led us to believe that a volt-frequency curve would look almost exponential, like the one on the screen now. That was our hypothesis. To be clear, we can push frequency higher with reference clock increases to 102 or 103MHz and can then sustain 4.2GHz at lower voltages, or even 4.25GHz and up, but that’s not our goal. Our goal is to plot a volt-frequency curve with just multiplier and voltage modifications. We typically run out of thermal headroom before we run out of safe voltage headroom, but if voltage increases exponentially, that will quickly become a problem.
There’s a new trend in the industry: Heatsinks. Hopefully, anyway.
Gigabyte has listened to our never-ending complaints about VRM heatsinks and VRM thermals, and outfitted their X470 Gaming 7 motherboard with a full, proper fin stack and heatpipe. We’re happy to see it, and we hope that this trend continues, but it’s also not entirely necessary on this board. That doesn’t make us less excited to see an actual heatsink on a motherboard; however, we believe it does potentially point toward a future in higher core-count Ryzen CPUs. This is something that Buildzoid speculated in our recent Gaming 7 X470 VRM & PCB analysis. The amount of “overkill” power delivery capabilities on high-end X470 boards would suggest plans to support higher power consumption components from AMD.
Take the Gigabyte Gaming 7: It’s a 10+2-phase VRM, with the VCore VRM using IR3553s for 40A power stages. That alone is enough to run passive, but a heatsink drags temperature so far below requirements of operating spec that there’s room to spare. Cooler is always better in this instance (insofar as ambient cooling, anyway), so we can’t complain, but we can speculate about why it’s been done this way. ASUS’ Crosshair VII Hero has the same VRM, but with 60A power stages. That board, like Gigabyte’s, could run with no heatsink and be fine.
We tested with thermocouples placed on one top-side MOSFET, located adjacent to the SOC VRM MOSFETs (1.2V SOC), and one left-side MOSFET that’s centrally positioned. Our testing included stock and overclocked testing (4.2GHz/1.41VCore at Extreme LLC), then further tested with the heatsink removed entirely. By design, this test had no active airflow over the VRM components. Ambient was controlled during the test and was logged every second.
The AMD R5 2600 and 2600X are, we think, among the more interesting processors that AMD launched for its second generation. The R5 1600 and 1600X received awards from us for 2017, mostly laying claim to “Best All-Around” processor. The 1600 series of R5 CPUs maintained 6 cores, most the gaming performance of the R7 series, and could still capably stream or perform Blender-style production rendering tasks. At the $200-$230 price range, we claimed that it functionally killed the quad-core i5 CPU, later complicated by Intel’s six-core i5 release.
The R5 2600 and 2600X have the same product stack positioning as the 1000-series predecessors, just with higher clock speeds. For specs, the R5 2600X operates at 3.6GHz base and 4.2GHz boost, with the 2600 at 3.4/3.9GHz, and the R5 1600X/1600 operating at a maximum boost of 4.0 and 3.6GHz, respectively.
Reviewing the AMD R7 2700X was done outside of normal review provisions, as AMD didn’t sample us. We’ve had the parts for a month now, and that has meant following development, EFI updates, and more as they’ve been pushed. We have multiple chips of every variety, and have been able to cross-validate as the pre-launch cycle has iterated. Because of the density of data, we’re splitting our content into multiple videos and articles.
Today’s focus will be the AMD R7 2700X and R7 2700 reviews, especially for live streaming performance versus the i7-8700K, gaming performance, and production (Blender) performance. Most importantly, however, we dedicate time to talk about the significant improvements that AMD has made in the volt-frequency department. At a given frequency, e.g. 4.0GHz, Ryzen 2000 operates at a heavily reduced voltage versus Ryzen 1. We’ll dig into this further in this review, but check back later for our R5 2600X and 2600 reviews (combined in one piece), including 2600X vs. 8600K streaming benchmarks. We’re also looking at VRM thermals, motherboard PCBs and their VRM quality, memory overclocking and scalability (in this content), and more.
There is a lot of confusion about AMD’s branding – Zen 2 vs. Ryzen 2 vs. Zen+. We’re calling these CPUs “Ryzen 2,” because they’re literally called “Ryzen 2X00” CPUs. This is not the same as the Zen 2 architecture, which is not out yet.
Note: For overclocking, we only OC one CPU of each core count – so just the R7 2700X or R7 2700, but beyond validation of maximum frequency, there’s no need to OC both and run each through 20 hours of testing.
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