Cooler Comparison Testing
Cooler Testing Methodology
To best gage the quality of the system coolers under review, system CPU temperature and cooling system audio measurements were taken with the CPU idle and under load. To replicate CPU idle conditions, the system was rebooted and allowed to sit idle for 10 minutes. To replicate a stress system load, AIDA64 System Stability Test was used in conjunction with EVGA OC Scanner X for 30 minutes per run. After each run, the system was shut down and allowed to rest for 10 minutes to cool down. Then the CPU cooler was removed, cleaned, and remounted to the CPU with fresh thermal paste applied. This procedure was repeated a total of six times for each cooler – three times each for the stock and overclocking speed runs on the X99-based system.
Temperature measurements were taken directly from the CPU thermistors using CoreTemp v1.61. Because of the volatile nature of the Haswell-E thermistor readings, the system temperatures were measured as follows. For idle temperatures, the highest recorded value was used for the run. For load temperatures, a series of three values were notated: the average (high and low) across all cores, the average (high and low) across the single highest core, and the high temperature.
To measure the performance of the water cooler kits tested, performance testing was done with the blocks in their default configuration only – with its logo readable with the board in a vertical orientation.
Note that the temperature values are reported as deltas rather than absolute temperatures with the delta value reported calculated as CPU temperature – ambient temperature. For all tests, room ambient temperature was maintained between 23-27C.
Intel X99-based Haswell-E System Testing
CPU Stock Speed Testing
The CPU stock speed testing was conducted with the BIOS defaults set for the CPU and Turbo Mode disabled, equating to a 3.0GHz CPU speed, 2133MHz memory speed, 3.0GHz ring bus speed, and 100MHz base clock. The Intel Speedstep functionality remained enabled for the duration of the testing to get realistic CPU idle performance conditions.
With the Haswell-E processor at stock speeds, there is little performance difference between the different water cooling kits let alone between the NexXxos XP3 Light and the Eisblock XPX blocks. Adding additional fans to the NexXxos kit also seemed to have little impact on either block's performance.
CPU Overclocked Speed Testing – Maximum water-cooled speed
The CPU overclocked speed testing was conducted with known stable settings from a previous board review with Turbo Mode disabled, equating to a 4.50GHz CPU speed, 2666MHz memory speed, 4.0GHz ring bus speed, and 100MHz base clock. The Intel Speedstep functionality remained enabled for the duration of the testing to get realistic CPU idle performance conditions.
Board voltage settings were configured as follows:
- CPU Core Voltage – 1.35
- DRAM Voltage – 1.23
- All other settings set to Auto or stock settings
In its default state with three fans and the NexXxos XP3 Light block, the system would not stabilize for more than 1 out of 4 runs. Similar behavior was seen using the Eisblock XPX block with the kit's default configuration. When an additional three fans were added to the NexXxos kit, the system's performance stabilized when using the Eisblock XPX block but remained unstable with the NexXxos XP3 Light block. Performance using the Eisblock XPX block dropped a mere 3C when paired with the NexXxos kit instead of the XSPX Photon kit. However, the stability issues encountered with the NexXxos XP3 Light block when paired with the NexXxos kit remains puzzling. The hypothesis, which the test data seems to support, for the NexXxos XP3 Light block's performance challenges is that the NexXxos kit's pump outbound flow path, radiator thickness, and fan speeds all collude to impact the performance of the block negatively. The Eisblock XPX CPU block is not as effected by the kit because it is a better performing block.
Sound Testing
When running at full speed, the NexXxos kit remains barely audible when using either the 3-fan or the 6-fan configuration with the fans running at full speed. This is mostly because of the lower speed ratings of the included fans – 1300RPM vs the 1600-2000 RPM of typical 120mm case fans.






Talk about not understanding
Talk about not understanding your market. A 2×5.25″ bay reservoir is a little bit passe these days no?
It would seem so, most new
It would seem so, most new enthusiast cases don’t even have 5.25 bays anymore.
maury, would you please
maury, would you please consider doing a review of a unit using quick connect couplings?
they would be the only thing that might, depending on your review, get me back to water cooling, which i gave up five years ago because of the hassle and the noise ironically
i have been using noctua’s since, but really am curious whether it would be relatively easy and hassle free with the quick connects?
i suspect there is a flow problem with them, but maybe some company has sorted out that issue
I use quick connects on my
I use quick connects on my test benched when doing the stand alone block reviews and have found that they do not impact performance. It really depends on which quick connects you use and what fittings / tubing you connect to them. I’ve had really good luck with the Alphacool HF quick connects and the Koolance quick connects as well. They do get pricey though…
maybe you can do a video of
maybe you can do a video of building a water cooling loop with quick connects for novices?
Perhaps passe a bit. However
Perhaps passe a bit. However keep in mind that kit with old blocks and old bay res are very old by now. It belong to the old Alphacool before they basically sack everybody and hired new people with new ideas.
I would agree that old XP3 block is very high restriction block and it can’t compete with top of the line performers like EK Supremacy, BP Summit or WC Heatkiller. But I find absolutely astounding that 1200 rpm e-loops can’t deal with heat on 60mm 9FPI (!)rad. That does not compute. I’m using exclusively Alphacool rads U and X-flows and on one PC I’m running Scythe 500 rpm fans in push only on 60mm 480 with single AC D5 and I have no issues whatsoever. e-Loops are superb fans even at sub 800rpm they are perfect for low FPI rads. I don’t know what’s wrong with the setup but it simply isn’t possible for 1200 rpm bionic fans to fail at removing heat from 9 FPI rad.
Heck I’m using e-Loops in push @750rpms on 16FPI X-Flows and they are perfect in every way. Either pump is crap or its crap. 😀
I think the performance issue
I think the performance issue seen in testing was more with the low flow of the pump in combination with the thickness of the radiator, made for a "perfect storm" of sorts…
Strange, that looks like the
Strange, that looks like the standard D5 VPP655 pump. Did you get a broken pump or something? Looking at your picture of the back of the res and the D5, it sure looks like their standard VPP655, a 1500 l/h pump. It should go to like 4800 rpm at the highest setting.
Datasheet for the D5 VPP655: https://www.alphacool.com/AtsdDataSheet/getDataSheet/articleId/10620
Product page:
https://www.alphacool.com/shop/sets-und-systems/alphacool-nexxxos/16245/alphacool-nexxxos-cool-answer-360-d5/ut-set
Edit: Looks like when I link directly to their English site, it changes to their German one in an incognito window. Needs to set a cookie or something by clicking the UK flag upper right corner.
The odd thing is that their
The odd thing is that their page lists two different max flow rates, depending on which page you look at. The Description page shows a flow of 350 l/h, while the tech spec page lists it at 1400 l/h. In any case, something was severely impacting the performance of the kit.
Found on this page on alphacool site:
https://www.alphacool.com/shop/pumps/alphacool-pumps/10620/alphacool-vpp655-single-edition
The 350 figure must be a typo
The 350 figure must be a typo in the description, they have miss-spelled words too here and there. Also mixing English/German in a chaotic manner? Sheesh, when will they fix their site… Anyway, the “Technische Details” tab say 1500, same in the datasheet.
This datasheet has both the VPP655 and the VPP644:
http://www.aquatuning.de/download/Alphacool-Laing-VPP655%20-%20TPP644-Datasheet.pdf
This one seems to be for the PWM controlled version:
http://www.aquatuning.de/download/Alphacool-Laing-VPP655%20-PWM-Datasheet.pdf
I don’t doubt that, performance was surely sub-par. That 90 degree bend at the back of the res that you mentioned on the podcast probably doesn’t help. And that XP3 block looks like a highly restrictive design, probably needs the pump at max rpm. Might work better with one of those high pressure DDCs like Swiftech MCP35X or MCP50X. I have a MCP35X and it can power through pretty much everything. Drawback is the DDC whine at high RPM, I’d take a D5 over that any day. All DDC pumps I’ve used have had that high pitched whine when over ~3000 RPM. A D5 is heaven in comparison, even at max RPM I can’t hear it outside the case.
Thanks for doing some custom loop stuff reviews, I appreciate it 🙂
Thanks for the additional
Thanks for the additional information Pholostan. I've updated some information in the review to better elaborate on the kit's performance mysteries as well as updating the pump flow rate numbers…