Thermalright Gets Back on Top with the Ultra-120

TESTING

Our socket 775 test bench was used to test the Ultra-120. Details of the system are outlined below. So far, seven heatsinks have been tested on this system: The Arctic Cooling Freezer 7 Pro, the Spire Verticool II, the Arctic Cooling Alpine 7, the Zalman CNPS8000, the Scythe Ninja, the Thermalright XP-120, and, most recently, the Apack ZeroTherm BTF80 & BTF90. No other SPCR heatsink test results are directly comparable with the results of this review. The Pentium 520 used in this test is cooler than most of Intel's soon-to-be-forgotten Prescott and Presler chips, but it is still 15-20W hotter than the P4-2.8 Northwood used in our socket 478 HS testing platform. On the other hand, it is also hotter than almost about every AMD processor on the market, not to mention Intel's new Core 2 Duo chips, which draw much less power than the Intel 520.

On the test bench...

Test Platform

• Intel 520 processor (P4-2.8 Prescott, 1 MB cache, 800 MHz FSB in 775 casing). The Thermal Design Power is 84.0W. The Maximum Power, as calculated by CPUHeat & CPUMSR, is 100.76W.
• AOpen i915Ga-PLF motherboard - Intel 915G Chipset; built-in VGA. Reviewed by SPCR.
• OCZ DDRAM PC-4000, 512 MB
• Fujitsu MHT2080BH 80GB notebook drive in Smart Drive (hard drive noise containment box).
• Antec Neo HE 430 power supply
• Arctic Silver Ceramique Thermal Compound
• Two-level open platform with foam damping feet. Motherboard on top; most other components below. Eases heatsink changes and setup.

Measurement & Analysis Tools

• CPUBurn processor stress software
• SpeedFan version 4.27 software to show CPU temperature
• A custom-built variable DC power supply that allows us to dial in the exact voltage to the fan
• B&K model 1613 sound level meter
• Seasonic Power Angel AC Power meter
• High resolution digital audio recording system

The Ultra-120 was tested with a Nexus 120mm fan — a very quiet, low airflow fan that has become our reference for heatsink testing. This may put the Ultra-120 at a slight disadvantage, since our test is biased to favor heatsinks that do well with low airflow. This reflects our desire for low noise. It is nearly impossible to build a quiet system with high airflow, so our emphasis on low airflow is appropriate.

Load testing was accomplished using CPUBurn to stress the processor, and the graph function in SpeedFan was used to make sure that the load temperature was stable for at least ten minutes.

The ambient conditions during testing were 16 dBA and 23°C.

TEST RESULTS

The acoustic characteristics of the Nexus 120mm fan have been documented extensive in previews articles and reviews, so a detailed analysis of the noise will not be provided here. Listening from a distance of one meter in our quiet lab, it is very quiet at full speed, barely audible at 9V, and completely inaudible below 7V. The noise is smooth and low and motor noise is almost nonexistent below 9V. In the 7~9V range where it is most likely to be used, the dominant noise is a slight whoosh of air turbulence.

As the numbers show, the Ultra-120 is an excellent performer, we do not doubt that it is capable of cooling our hot test processor inaudibly, as the temperature is acceptable even at 5V. Unless heavy overclocking is involved, the only current processors that may need a faster fan are Intel's hot 8xx and 9xx series, which we'll be happy to wave goodbye to soon.

COMPARISON

Just how good is performance? A direct comparison, using the same fan, is really the only way to know. Fortunately, we have tested our current champion, the Scythe Ninja, as well as a Thermalright XP-120 using the same fan on the same test bed, so it is easy to see which heatsink performs best:

In this case, numbers tell the story better than words. The Ultra-120 beat the Ninja at every voltage level except the lowest, where the two were equal. The victory wasn't large or earth-shattering, just two or three degrees, but it was there. The XP-120 — a one time champion at SPCR — is a distant third in all cases, clearly unable to compete at such low airflow.

As exciting as it is to crown a new heatsink king, the results here bear putting into perspective. The Ultra-120 did not win by a knockout the way the Ninja did when it first showed up. Its victory was hard-fought, and it's quite likely the results could have been different in a slightly different setup. And — let's be honest — the Ninja is already good enough to cool the vast majority of systems without increasing system noise. The Ultra-120 can make the same claim, but the difference isn't enough to justify an upgrade from one to the other.

If noise is not a concern, we wholeheartedly recommend the Ultra-120. The difference between the Ultra-120 and the Ninja was greatest when the fan was at full speed, which suggests that the gap between the two would be wider with a higher airflow hand. On the other hand, the Ninja is specifically designed for fanless operation, and is almost certainly a better choice for a passively cooled processor.

NOISE RECORDINGS IN MP3 FORMAT

Nexus 120mm fan: 5V-7V-9V-12V, 5s Ambient between levels: One Meter, One Foot

Comparatives:

APack ZeroTherm BTF80 & BTF90: 5V-7V-9V-12V, 5s Ambient between levels: One Meter, One Foot

Arctic Cooling Alpine 64: 5V-7V-9V-12V, 5s Ambient between levels: One Meter, One Foot

Scythe Mine w/ stock fan: 5V-7V-9V-12V, 5s Ambient between levels: One Meter, One Foot

FINAL CONCLUSIONS

The Ultra-120 is the most efficient heatsink we've tested, and ultimately, that's what counts. Despite concerns over fin spacing, it managed to beat the Scythe Ninja, even with our tough low-airflow test. Unless you're planning to cool the CPU passively, you can't do better than the Ultra-120.

The installation system is simple and easy to use, and should have full support for AM2 in the near future. Until then, the K8 clip for the HR-01 is a good substitute.

The biggest drawback is that with the K8 mounting hardware, the heatsink fan's orientation is dictated by the orientation of the motherboard's heatsink retention bracket. If it runs "east-west", the fan will be positioned to blow towards the back panel. This is the preferred orientation, because the hot air will be exhausted by the back panel case fan than almost every system will have. If the HS retention bracket orientation is "north-south", the fan on the Ultra-120 will blow up towards the power supply, which may cause its internal fan to ramp up in speed and become noisier under load.

The lack of a fan may also be a drawback for some, although most silencers will want to pick their own anyway. Just remember to choose a fan with open screw mounting flanges — or be prepared to modify one with closed flanges. The only other quibble is that it may be too large to fit into some systems, but the same applies to just about every high-end heatsink these days.

A year after yielding the cooling throne to the upstart Scythe, Thermalright is back on top. We're happy to see it: Competition is sure to spur more development and perhaps help prices fall.

Much thanks to Thermalright for the review sample.

* * *

Articles of Related Interest

* * *

Comment on this article in our Forums.