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
SmokeRngs - Wednesday, February 28, 2007 - link
The information you wanted is there. Why are you complaining? There are plenty of people that don't care about the information you want but do want the information you deride. Both are there in a clear and concise manner for those that want to see one or both.
shabby - Monday, February 26, 2007 - link
People who buy $50 heatsinks dont buy them because they're quiet, they buy them so they can overclock their cpu's. Plus they probably stick higher cfm fans, so they're not quiet anymore.Zambien - Monday, February 26, 2007 - link
I disagree. When I bought my Zalman 7700cu for my current PC, the main reason was that it would provide similar cooling to my current HSF, with less noise. I didn't like the fact that my computer sounded like a jet engnine. I'm sure some people fall into the category, but others do not.cujo - Monday, February 26, 2007 - link
why wouldn't you test with overclocks?arswihart - Monday, February 26, 2007 - link
Not to mention they are talking about 50Mhz differences in OC to separate better and lesser performing heatsinks. Come on, that isn't even a significant difference. Did they repeat the result on multiple systems, or just the one. Does it matter? Of course not.arswihart - Monday, February 26, 2007 - link
A heatsink doesn't do anything magic to give you higher OC's, it gives you lower temps, which will then let you OC higher.Measuring a CPU's OC is looking at data that is a step removed from what you should be looking at, which is simply the temperature. I could care less what they get to OC to, it will be almost certainly different for anyone who buys the heatsink.
The only thing that I think is worth taking away from any heatsink review is: installation caveats, temps, and noise.
shabby - Monday, February 26, 2007 - link
I find it funny that the infinity cant beat the tt120, does it have thicker heatpipes or what. What part of the tt120's construction make it better then other beefier/bigger coolers?Superdoopercooper - Monday, February 26, 2007 - link
The first rule in A-B testing is to hold EVERYTHING constant except for the items being examined/tested.Therefore, in ALL of your heatsink reviews, the system down to the THERMAL COMPOUND should remain fixed, even if the heatsink ships with some "higher end" stuff.
I think it would be wise to pick ONE thermal compound and use it on EVERY heatsink test. Then you are testing the performance of the heatsink (i.e. Heatsink #1 is better than Heatsink #2, with no exceptions), and not the thermal grease + heatsink.
I would hate to think that heatsink #1 was the best, but only because it shipped with better compound than another. I think many people ponying up for these higher-$$ heatsinks will pony up $6 for some good thermal grease.
Then, if you want to do an additional test that comments on the performance of the included thermal grease, that would/could be helpful to potential buyers.
Wesley Fink - Monday, February 26, 2007 - link
I can easily link you to a review from a respected source that proves toothpaste and Kraft Vegemite are superior in cooling to Arctic Silver 5 :-) I have tested many thermal compounds and found little differnece among the quality products. That conclusion was a rude awakening for me. I have found much more variation in perfromance in how the thermal grease was applied than I have ever found in the thermal compounds themselves.Thus far, all of the tests have used our standard silver-colored (but no real silver content) tube thermal compound except the Thermalright MST 6775 and the Zalman pair. These came with top thermal grease, and yet none of the three beat our Tuniq or this Infinity. If the cooler company cares enought to supply a premium thermal compound we test with that compound.
Superdoopercooper - Monday, February 26, 2007 - link
If it is true that all thermal compounds are nearly equal, then I guess that's fine. I would like to see the link, actually.That still doesn't change the fact that the best A-B testing holds EVERYTHING constant except the single item being tested.
Since AT is the site I hold in the highest regard in terms of info on computer components, I thought I'd just throw up my $0.02 on ways to maybe make these tests "better" and/or more scientific.
Could just be my test engineering background talking. :-P