Introduction to the Noctua NH-D15S CPU Cooler

Noctua – This is a brand that you have likely heard of throughout the years, but if not, you really need to look into them more.  Noctua is well known for their highly successful and high quality CPU coolers, cooling fans, and thermal pastes.  It has been a while since we’ve looked at a product from Noctua, so today we’re going to take a look at a cooler that is nearly identical to one that we previously reviewed, but with a couple revisions.  This particular cooler, the NH-D15S, was originally released on August 28, 2015, so it has been around for a while, but still performs like a king. Noctua NH-D15S Noctua’s NH-D15S is darn near identical to the NH-D15, so in this review I expect nearly identical performance.  We’re going to trim out the packaging and installation pages, but if you’re interested, you can view the NH-D15 installation here – nothing changed. So what’s so great and different about the NH-D15S vs. the NH-D15?  Well, the first thing that I noticed is that the NH-D15S only comes with a single fan, but an identical model fan – NF-A15 PWM.  This cooler was designed to be 100% compatible with the various modern socket / PCIe placement and RAM (up to 65mm tall) that’s on the market, which is one of the reasons why Noctua omitted one of the fans from the kit.  Rest assured, you can still hook up a second fan to the cooler, but like the original NH-D15, it may need to be placed much higher when placed in a push configuration above the memory.  In my particular scenario, the memory that I'm using is extremely tall, forcing me to lift the fan a bit higher than usual.  Fortunately, attaching the side panel on my particular chassis was fine, but you may have an issue if you have RAM with very tall heat spreaders attached. Noctua NH-D15S   What else?  Tied in with the single fan for compatibility, the base of the cooler is asymmetrical, which allows for better PCIe compatibility.  Why does this matter?  Well, with some modern boards, the PCIe slots tend to migrate closer to the CPU socket, which makes coolers like the NH-D15 block it.  Noctua’s solution to that was to adjust the placement of the base so the cooler sits up a bit higher on the motherboard. Noctua NH-D15S vs NH-D15 Both coolers feature cutouts in the cooling towers, which allow taller RAM modules to be installed, because after all, the NH-D15 and NH-D15S are massive air coolers!  The cooling stacks are completely identical, both feature 6 nickel-plated heat pipes, both have identical mounting systems, and more importantly, both feature a 6-year warranty from Noctua. The pricing of the NH-D15S is currently going for $74.97 shipped on Amazon, while the NH-D15 will run you $87.77 shipped.  Should you want another NF-A15 fan to go with the NH-D15S, you can pick that up for $20.92 shipped on Amazon – I would highly recommend it if you need the NH-D15S over the NH-D15.  Noctua did include an additional NF-A15 fan for us to test with, so be sure to read on to see how the performance was impacted. Noctua NH-D15S vs NH-D15 Specifications
NH-D15S NH-D15
Socket Compatibility Intel: LGA2011-0 & LGA2011-3 (Square ILM), LGA1156, LGA1155, LGA1151, LGA1150 AMD: AM2, AM2+, AM3, AM3+, FM1, FM2, FM2+ (backplate required) Intel: LGA2011-0 & LGA2011-3 (Square ILM), LGA1156, LGA1155, LGA1151, LGA1150 AMD: AM2, AM2+, AM3, AM3+, FM1, FM2, FM2+ (backplate required)
Height (without fan) 160 mm  160 mm
Width (without fan) 150 mm 150 mm
Depth (without fan) 135 mm  135 mm
Height (with fan) 160 mm  165 mm
Width (with fan) 150 mm  150 mm
Depth (with fan) 135 mm  161 mm
Weight (without fan) 980 g  980 g
Weight (with fan) 1150 g  1320 g
Material Copper (base and heat-pipes), aluminium (cooling fins)
Fan compatibility 140x150x25 (with 120mm mounting holes), 140x140x25 (with 120mm mounting holes), 120x120x25
Warranty 6 Years
Fan Specification
Fan Model 1x Noctua NF-A15 PWM 2x Noctua NF-A15 PWM
Max RPM 1500 RPM (+/- 10%)
Max Speed (LNA) 1200 RPM (+/- 10%)
Min RPM 300 RPM (PWM, +/-20%)
Max Airflow 82.5 CFM
Max Airflow (LNA) 68 CFM
Max Noise 24.6 dBA
Max Noise (LNA) 19.2 dBA
MTBF 150,000 Hours
  As you can see from the above specifications, these coolers are completely physically identical. Again, packaging and installation are almost 100% identical between the NH-D15S and the NH-D15, so we’re going to skip those pages and move right onto the test system specifications, followed up by some benchmarks.  What we're going to leave you with here is a couple photos of the packaging and included accessories. [gallery columns="4" link="file" ids="188616,188619,188618,188617,188624,188620,188622,188621,188623,188635,188636"] Feel free to read the NH-D15 review for further information on the packaging and installation.

The Test System

Before we take a look at the performance numbers, let’s take a brief look at the test system that was used.  All testing was done using a fresh install of Windows 10 Professional 64-bit and benchmarks were completed on the desktop with no other software programs running. ALL COOLERS will be using Noctua NT-H1 thermal compound, which requires zero cure time. Noctua NH-D15S - Installed Intel Z97/LGA1150 Platform The Intel Z97 platform that we used to test these coolers was running the MSI Z97 Gaming 5 motherboard with BIOS version 1.D that came out on 02/17/2016.  We will be sticking with this version of the BIOS between all coolers.  The processor used, the Intel Core i7 4770k, will be using the stock frequency of 3.5GHz with turbo boost enabled, which can boost it up to 3.9GHz.  Low power state is enabled and the CPU frequency and v-core are set to AUTO, just like they were out of the factory. When we do our overclocking, the 4770k will be overclocked to 4.4GHz at 1.1850 volts, which is just a hair over the stock 1.1755 volts read from Core Temp.  This particular 4770k may have a little more in it, but I had difficulties with going above 4.5GHz while retaining reasonable temperatures, so I settled on 4.4GHz.

Noctua NH-D15S Benchmarking & Overclocking

In the benchmarks that will be run, we used an Intel 4770k clocked at 3.5GHz with Turbo Boost and the low power state enabled.  Turbo Boost allows the 4770k to hit up to 3.9GHz right out of the box.  Stock results will be utilizing auto for the multiplier and v-core, which reads 1.1750v in Core Temp, and overclocking will utilize manually entered multiplier and voltage numbers.  In this case, our Intel Core i-7 4770k was able to obtain a 4.4 GHz overclock at 1.185 volts. To record temperatures, we used Core Temp v1.4 to monitor and record temperatures.  For our idle temperature, we will average the readout across all four cores from Core Temp.  When stress testing, we will use Core Temp’s Max number and average all four cores. Slimming down on the benchmarks from previous reviews, we’ll be strictly using AIDA64 to stress the CPU and no games.  Within AIDA64, we will be running the System Stability Test and choosing the Stress CPU, FPU, Cache, and System Memory tests for thirty minutes.  This will peg all four cores and eight threads to 100%, which will help us to understand exactly how hot this CPU can get with each cooler. Ambient temperature during all testing was 72 degrees Fahrenheit. Since this is an older cooler, we’re just doing a comparison between the NH-D15 and NH-D15S.  We have also decided to switch from Prime95 to AIDA64 going forward, as we feel it will provide even better results.  In the future cooler reviews, we will add a few choice coolers to the charts for comparison, but again, this time it is strictly between the two Noctua coolers. ALL COOLERS will be using Noctua NT-H1 thermal compound, which requires zero cure time.   Idle  Noctua NH-D15S - Idle   AIDA64 @ 3.9GHz  Noctua NH-D15S - AIDA64 - Stock   AIDA64 @ 4.4GHz  Noctua NH-D15S - AIDA64 - Overclocked   Overall Results:  Quite frankly, between the two Noctua coolers I expected nearly identical results with a 2-fan configuration, and that’s exactly what I saw.  When it comes to adding one additional fan, it could very well be a decent investment for slightly better cooling capabilities.

NH-D15S Noise Testing

Noise testing was a highly requested item by our readers, and with this new system, we have those numbers for you! To obtain our noise numbers, we’re using an Extech 407750 Sound Lever Meter with the wind screen on.  This meter is placed six inches from the top side of the chassis on a level tripod. (See picture)  It and the PC case are placed in the exact same spot with the side panel off, as to not taint results, because the movement of just one inch can skew results. Noctua NH-D15S All noise readouts are obtained at the end of the test (Idle or AIDA64) to allow the system sufficient time to get “settled in.”  Ambient noise readout was gathered from only the system fans running – not any component in the cooler. AMBIENT NOISE:  39.1 dBA Noctua NH-D15S - Noise   Overall Results:  Again, as expected the coolers provided nearly identical results with the 2-fan configuration.  What I find rather interesting, is that the sound meter actually read lower with two fans in place vs. a single.  I verified RPMs weren’t different between the two, so I’m a bit dumbfounded.

Noctua NH-D15S CPU Cooler - Final Thoughts and Conclusion

Noctua released the NH-D15S well over a year ago, but since the NH-D15 was such a great cooler, we opted to compare the two side-by-side.  Truth be told, we expected nearly identical results when it came to a dual-fan configuration.  However, since the NH-D15S only comes with a single fan, we were interested in seeing the results between the two. Noctua NH-D15S Installation of this cooler was simply a breeze.  I really like Noctua’s mounting system that is included with this kit, and I wish other manufacturers would follow suit with something so easy. [gallery columns="4" link="file" ids="188626,188627,188628,188629,188630,188631,188632,188633,188634"] Performance of the NH-D15S vs. the NH-D15 was almost 100% identical, while in a dual-fan configuration anyway, as we expected and as it should be.  The NH-D15S does only come with a single fan from the factory, so you will need to purchase a second fan if you would prefer even better performance.  You’ll be able to grab a second fan for $20.92 shipped on Amazon.  When the cooler was only in its single-fan configuration, it actually performed quite well, though a second fan does give it that little extra edge. Noctua NH-D15S The pricing of the NH-D15S is currently going for $74.97 shipped on Amazon, while the NH-D15 will run you $87.77 shipped.  Both coolers feature an outstanding 6-year warranty from Noctua. Now, since we did originally recommend the NH-D15 cooler, this one undoubtedly will receive the same award.  However, keep this in mind, that if you do not have any PCIe placement issues on your motherboard, you should absolutely skip this cooler and go for the NH-D15.  Why do you say?  Because it already comes with dual fans and costs less than the NH-D15S with an additional fan purchased alongside.   LR Recommended Award   Legit Bottom Line:  There isn’t a whole lot new or special about Noctua’s NH-D15S CPU cooler, however it still performed very well and darn near identical to the NH-D15 – as it should.