Scythe Infinity: 5 Heatpipes and Silent 120mm Fan
by Wesley Fink on February 26, 2007 12:05 AM EST- Posted in
- Cases/Cooling/PSUs
Scaling of Cooling Performance
The Scythe Infinity was an excellent performer in CPU cooling at stock speeds. However, as overclocks were raised, the performance of the single fan (stock) Infinity was below average. The Infinity reached relatively high overclocks, topping out at an average 3.83Ghz, but the cooling temperatures were higher than expected for a top cooler. It appears that this performance curve is mostly the result of the very low noise 1200 RPM fan Scythe ships with current Infinity coolers.
Further evidence that the low-noise fan is holding back cooling performance during overclocking can be seen by comparing the two fan Scythe Infinity results. Using two of the low-noise Scythe fans in a push-pull configuration significantly lowers the CPU temperature. In this configuration one fan pushes air through the cooling fins while the fan on the opposite side pulls the air. In other words both fans are blowing in the same direction toward the back of the case.
At 3.73GHz the retail HSF is running at 56C, compared to 43/41 with the Infinity in stock/dual fan setup. At every speed the idle performance is much improved with the push-pull fan setup. The delta becomes greater as the overclock increases. At 3.83GHz the idle with the stock single fan is 51C compared to the push-pull dual temp of 44C - a significant 7C improvement in cooling.
As described already, stress testing utilized the Far Cry River demo in a continuous loop for 30 minutes. Cooling efficiency of the Scythe Infinity under stress conditions was then compared to the retail HSF and other recently tested CPU coolers. Once again we tested both the stock and push-pull fan configurations.
By 3.83 GHz, which is the highest overclock the stock Infinity could reach with stability, the Tuniq is at 50C compared to the stock Infinity at 67C. Add a second fan to the Infinity with push-pull cooling, however, and the load temperature at 3.83GHz drops to 60C. What's more the dual fan Infinity can overclock higher - to 3.90GHz - to match our highest overclock on air with this CPU. That makes the push-pull Scythe Infinity the first air cooler to overclock to the same 3.90GHz reached with the Tuniq, which is excellent performance.
As stated many times, the overclocking abilities of the CPU will vary at the top, depending on the CPU. This particular CPU does higher FSB speeds than any X6800 we have tested, but the 3.9GHz top speed with the Tuniq is pretty average among the X6800 processors we have tested with Tuniq cooling. A few of the other processors tested with the best air coolers reach just over 4 GHz, but the range has been 3.8 to 4.0GHz. Stock cooling generally tops out 200 to 400 MHz lower, depending on the CPU, on the processors tested in our lab.
The Scythe Infinity was an excellent performer in CPU cooling at stock speeds. However, as overclocks were raised, the performance of the single fan (stock) Infinity was below average. The Infinity reached relatively high overclocks, topping out at an average 3.83Ghz, but the cooling temperatures were higher than expected for a top cooler. It appears that this performance curve is mostly the result of the very low noise 1200 RPM fan Scythe ships with current Infinity coolers.
Further evidence that the low-noise fan is holding back cooling performance during overclocking can be seen by comparing the two fan Scythe Infinity results. Using two of the low-noise Scythe fans in a push-pull configuration significantly lowers the CPU temperature. In this configuration one fan pushes air through the cooling fins while the fan on the opposite side pulls the air. In other words both fans are blowing in the same direction toward the back of the case.
At 3.73GHz the retail HSF is running at 56C, compared to 43/41 with the Infinity in stock/dual fan setup. At every speed the idle performance is much improved with the push-pull fan setup. The delta becomes greater as the overclock increases. At 3.83GHz the idle with the stock single fan is 51C compared to the push-pull dual temp of 44C - a significant 7C improvement in cooling.
As described already, stress testing utilized the Far Cry River demo in a continuous loop for 30 minutes. Cooling efficiency of the Scythe Infinity under stress conditions was then compared to the retail HSF and other recently tested CPU coolers. Once again we tested both the stock and push-pull fan configurations.
By 3.83 GHz, which is the highest overclock the stock Infinity could reach with stability, the Tuniq is at 50C compared to the stock Infinity at 67C. Add a second fan to the Infinity with push-pull cooling, however, and the load temperature at 3.83GHz drops to 60C. What's more the dual fan Infinity can overclock higher - to 3.90GHz - to match our highest overclock on air with this CPU. That makes the push-pull Scythe Infinity the first air cooler to overclock to the same 3.90GHz reached with the Tuniq, which is excellent performance.
As stated many times, the overclocking abilities of the CPU will vary at the top, depending on the CPU. This particular CPU does higher FSB speeds than any X6800 we have tested, but the 3.9GHz top speed with the Tuniq is pretty average among the X6800 processors we have tested with Tuniq cooling. A few of the other processors tested with the best air coolers reach just over 4 GHz, but the range has been 3.8 to 4.0GHz. Stock cooling generally tops out 200 to 400 MHz lower, depending on the CPU, on the processors tested in our lab.
Facebook
Twitter
RSS
39 Comments
View All Comments
dtanner - Monday, February 26, 2007 - link
By keeping the tower short, you are keeping the mass of the tower closer to the mobo and thus reducing the stress on the push pins. As another poster has stated, with this much mass I would definitely spend the extra $10 and get the UNIVERSAL RETENTION KIT "SCURK1".chienpourri - Monday, February 26, 2007 - link
Juste a suggestion, Scyte sells a UNIVERSAL RETENTION KIT "SCURK1" that anyone can find for around 10$, it comes with a backplate and everything. As the reviewer said, I would feel very uncomfy sitting the Infinity with only brackets... However using this kit it would fix the problem. The only downside I can find is the increased cost, but 10$ for security sounds good to me!orion23 - Monday, February 26, 2007 - link
Yeah...That!orion23 - Monday, February 26, 2007 - link
Hi!Great test guys!
I love how Anandtech started testing and reviewing other PC components.
You guys are doing great so far! Keep them coming...
And don't forget Power Supply Units!
Calin - Monday, February 26, 2007 - link
I find it somewhat to be understood - as the air would flow worse inside the cooler, part of it will flow out of it using the lateral spaces - as such, contributing very little or not at all to cooling.I wonder how much would single fan cooling improve if the air flow would be restricted in escaping by the sides. If so, what the performance would be with a push-pull configuration and lateral restrictions on air movement (escape)?
Jjoshua2 - Monday, February 26, 2007 - link
What I want to see is a more head to head test, with either the Tuniq using fans at the Infinity noise level, or the Infinity getting two higher powered fans, to see which wins.What I am interested in is the best performing silent/near silent fan & heatsink combo.
But overall, I liked the article thanks!
Wesley Fink - Monday, February 26, 2007 - link
We appreciate your suggestion, but we make every effort to test CPU coolers as they are packaged if at all possible. It would be a massive effort to try to go through an assortment of fans, find those singles and pairs that noise match and then replace fans supplied with the coolers with these matched singles and pairs. HSFs like Zalman have embedded fans which can't be swapped, and many top coolers use fan sizes with more limited selections than the 92mm or 120mm fan sizes.You have an interesting idea for an article on silent cooling, but it does go beyond the bounds of benchmarking and comparing performance of CPU coolers.
crimson117 - Monday, February 26, 2007 - link
What is the ambient temperature in the room during testing?Does the room get hotter after a few hours of testing, perhaps skewing temperatures higher for models tested at the end of the day?
Wesley Fink - Monday, February 26, 2007 - link
The ambient temperature of the room is 69F (21C) and is reasonably consistent. When running many computers in benchmarking the temperature may rise to 75F, but we check the temperature and turn off other systems during cooler testing.