Archive Home arrow Reviews: arrow Cooling arrow Corsair Hydro H70 Liquid CPU Cooler

Corsair Hydro H70 Liquid CPU Cooler E-mail
Reviews - Featured Reviews: Cooling
Written by David Ramsey   
Tuesday, 08 February 2011
Table of Contents: Page Index
Corsair Hydro H70 Liquid CPU Cooler
Closer Look: Corsair CWCH70
Corsair CWCH70 Detailed Features
Heatsink Test Methodology
Testing and Results
Final Thoughts and Conclusion

Testing and Results

For this test, I used the following heat sinks in addition to the Thermaltake Jing:

  • Thermalright Venomous X
  • Cooler Master V6 GT
  • Prolimatech Super Mega
  • Corsair Hydro Series H50
  • Corsair Hydro Series H70
  • Coolit ECO A.L.C.
  • Coolit Vantage A.L.C.

For heat sinks without a stock fan, I used a Thermalright TR-FDB-12-1600 fan, which puts out 63.7CFM at 28dBa according to Thermalright. This mid-range fan provides good air flow and reasonable noise levels. For "apples to apples" testing, where each heat sink is tested with the same fan, I used a Delta AFC1212D. This high-performance PWM fan is rated at 113CFM at a claimed 46.5dBa at full speed...which means that while it moves quite a bit of air, it's very loud.

The Intel Core i7-950 I used in this test runs much hotter than the Core i7-920 I'd used previously. At 1.35 volts, with a BCLK of 175Mhz, the 4,025Mhz CPU pumped out enough heat to stress the very best heat sinks. AIDA64 would report throttling once any single core reached 100 degrees Celsius; any throttling resulted in cancelling the test and recording a "FAIL". Although this overclocked and overvolted Core i7-950 represents an extreme, these are expensive, high-end heat sinks.

The chart below summarizes the results with the stock fans (hotter temperatures towards the top of the chart, and cooler temperatures towards the bottom). The twin-fan units (the Cooler Master V6 GT and the Corsair H70) have a real advantage here, since their dual fans move more air than the stock single fan of any of the other units. The Corsair H70's fans at their default 2,000RPM level move a lot of air together, but also generate a fair amount of noise. At the 1,600RPM level achieved with the in-line resistor cables, the noise level is much reduced, with a relatively minor performance hit. While Corsair says the stock H50 fan provides about 50CFM, they do not provide any specifications on the H70 fans other than their dimensions, so the official air flow, static pressure, and noise levels are a mystery, which is annoying if you are considering replacing the fans.

Stock Fan Tests

Heat Sink

Thermal Difference
(degrees Celsius)
from H70 (high)
Coolit ECO A.L.C. 75.2 +9.9
Thermaltake Jing 73.7 +8.4
Corsair H50 73.1 +7.8
Coolit Vantage A.L.C. (extreme) 73.0 +7.7
Corsair H70 (low) 67.7 +2.4
Prolimatech Super Mega 67.2 +1.9
Corsair H70 (high) 65.3 +0.0
Thermalright Venomous X 63.0 -2.3
Cooler Master V6 GT 61.2 -4.1

With its dual, high performance fans (according to Cooler Master, each fan is rated at 93CFM at full speed, for an aggregate airflow of over 180CFM) the Cooler Master V6 GT takes the lead here, keeping the blistering hot Core i7-950 4.1 degrees Celsius cooler than the H70 with its fans running at full speed. The Cooler Master H70 also benefits from dual fans, but perhaps they're not moving quite as much are as the V6 GT fans (we don't really know since Corsair does not provide airflow numbers). Dropping the H70's fan speed to 1,600RPM with the included resistor cables makes the system much quieter at the cost of 2.4 extra degrees of processor temperature.

What's interesting in this chart is the 5.3-degree "break" between the Coolit Vantage A.L.C. and the Corsair H70, which neatly separates the coolers into "lower performance" and "higher performance" groups.

Delta High Speed Fan Tests

Heat Sink

Thermal Difference
(degrees Celsius)
from H70 (high)
Thermaltake Jing 69.7 +5.0
Corsair H50 68.1 +3.4
Coolit Vantage A.L.C. 67.8 +3.1
Corsair H70 64.7 +0.0
Coolit ECO A.L.C. 64.3 -0.4
Cooler Master V6 GT 59.5 -5.2
Prolimatech Super Mega 59.4 -5.3
Thermalright Venomous X 58.0 -6.7

With the Delta high-speed fan, our lineup changes. The Coolit ECO A.L.C. moves from the bottom to the chart to just beyond mid-pack, improving by almost 11 degress. The Prolimatech Super Mega and Thermalright Venomous X jump to the to lead, and the Corsair H70 drops back a few places, although its actual performance is very slightly (0.6 degrees Celsius) better. This is something I've seen before when replacing a dual-fan cooler's stock fans with a single fan: the performance advantage of even very noisy, high speed fans is minimal if it exists at all. Note that in this scenario, the Coolit ECO A.L.C. with its much thinner radiator actually performs better than the H70. I think the 48mm-thick radiator of the H70 works best with dual fans to push the air through all those fins. (Again, it would be nice to know the air flow and static pressure specifications of the included fans.)

In this chart, there's a 4.8-degree "break" between the Coolit ECO A.L.C. and the Cooler Master V6 GT. In this "apples to apples" comparison, the three top-performing air coolers are obviously in a class of their own. While all-in-one water cooling kits are making progress, Big Air still has a significant advantage in this scenario.



# Idea.Succellus 2011-02-08 02:08
You could put a symbology of all your awards so newcomers know how good the product is according to the award.
Report Comment
# RE: Idea.Olin Coles 2011-02-08 08:26
The final score is a 10-point value, and should be an easy indicator for newcomers.
Report Comment
# RE: Corsair Hydro H70 Liquid CPU CoolerRobert17 2011-02-08 05:14
I purchased an H50 last year and have it configured to exhaust outside the case and find it's performance acceptable on a day-to-day basis. It's certainly an improvement over the stock CPU coolers, and reasonably priced for that uptick.

I'll add to your note regarding the 'secret' pump performance. Besides the fluid flow, the fluid itself makes a difference and custom systems certainly have another advantage here. Different fluids and additives can increase heat transfer by decent margins. So if one is involved in serious overclocking, an open system has many advantages. But the simple and sealed packages such as the ALC and Corsair offerings are, as you said, a reliable, quiet, affordable, and easy way to increase heat displacement from the CPU.

Also note, the dual fan, push/pull configuration mounted to the radiator doesn't necessarily increase the CFM across the radiator by doubling the air flow (think of a fan as a pump for the fluid named 'air'). The same air moves through one fan, across the radiator, and then through the second radiator, fan speeds being equal. The air doesn't 'hover' around the radiator but is drawn more efficiently across the fins, and consistent pressure is maintained. To move more air, the fan speeds must be increased. Just as with any fluids, to increase flow, pumps must increase the fluid pressure. Adding more in-line pumps (fans) that all run at the same RPM doesn't increase flow, just maintains consistent pressure.
Report Comment
# RE: RE: Corsair Hydro H70 Liquid CPU CoolerDavid Ramsey 2011-02-08 11:46
A push-pull configuration probably won't double airflow, but it will certainly help compared to a single fan. For "thin" radiators a single fan of "x" CFM will probably provide more airflow than a push-pull config where each fan is "x/2" CFM, but I think this would not be the case with the H70's double-thick radiator, which offers much more resistance to airflow.
Report Comment
# h50 performs betterBunzing 2011-02-08 06:30
I switched motherboards a couple of weeks ago and wrecked the backplate of the h50 when I had to take it of. Corsair for some reason put superglue on it and it didn't come of without force. So I thought I'd buy an h70 and get corsair to send me a new backplate and sell the h50. Don't think I'll be getting the new backplate though since corsair won't respond to emails.

The h70 however has to be placed in the top of my cooler master cosmos s because otherwise it would interfere with the side intake fan. It runs on 1600 rpm and makes a lot more noise then my h50 (also had two fans) and runs 5C higher then the h50. Both are configured as exhausts btw.

I don't understand what causes this difference. Offcourse the sound is understandable since I had two of my own thermaltake iscg fans on it running at 1000 rpm! But still the h70 with 1600 and bigger radiator is 5C above the h50 with 38C in idle and around 42c when playing games.

If or when I get the backplate I'll do some testing wether or not there still is a big difference when I put it up in the same configuration and use the same fans as the H70.
Report Comment
# RE: h50 performs betterDavid Ramsey 2011-02-08 11:47
I'm surprised the H70 is turned in higher processor temps than your H50. If you feel ambitious, it would be interesting to remove your Cosmos' side fan, put the H70 in the back, and see if that makes a difference.
Report Comment
# RE: RE: h50 performs betterBunzing 2011-02-13 09:33
I'll try that when I have the time. I'm curious to see if that makes the difference.
Report Comment
# RE: RE: RE: h50 performs betterBunzing 2011-03-01 03:22
Well, I placed the h70 in the back with the side off and it did shave the temps a little when it comes to case temperture but the cpu only dropped like 1c. Now i've got my h50 in the back with a thermaltake iscg fan as a second fan at 1000rpm and I have to come back on the temperture as it does run a around 4 to 5c of degrees higher than the h70 (nothing like the diference i've seen in most benchmarks where it's more like 10c). For me the amount of decibels the h50 runs lower on is the deciding factor. The temps never hit 45c, so i'm good.
Report Comment
# Area mattersRealNeil 2011-02-08 06:57
For better heat dissipation they should have gone for more radiator surface area instead of a thicker radiator. A 120mmX240mm area would cool more efficiently. I realize that it would affect the fitment into a number of cases, but many cases have incorporated a spot for two 120mm fans on the topside already. Since heat normally rises, placement of such a radiator at the top of a case, exhausting the hot air through the top would just work better. I have an Asetek-LCLC (low cost liquid cooling)and a Corsair H50 here, (both are MADE by Asetek, and both are identical too) I have them in push/pull with high flow and quieter fans on each of them. They are excellent cooling solutions for my two i7-870's, both running @3.93GHz.
Report Comment
# RE: Area mattersDavid Ramsey 2011-02-08 11:52
Heat-- well, heated fluids-- do indeed rise, but even the feeblest fan will provide an order of magnitude more air flow than the convection currents off a hot radiator, so I don't think radiator positioning will make a noticeable (or even measurable) difference in performance (although another commenter here who's mounted his H70 rad at the top of his case is getting worse performance than with his H50 mounted at the back, which is the opposite of what you'd expect).

A double-thick 120mm radiator offers the same surface area as a single-thickness 120x240mm radiator, although I think the latter would probably have a performance advantage due to better air flow.
Report Comment
# Koolance erm-2k3u + cpu-350 + ocz freezeJuanPabloC 2011-02-08 13:01
my i7 920 @ 2.8ghz works at 21°c with 11 blocks, at "full" load (WinRar benchmark test)cpu never goes over 28°c. (43°c at the cores)... measured with HWMonitor from

60°C ? ... at the cores?
Report Comment
# RE: Koolance erm-2k3u + cpu-350 + ocz freezeOlin Coles 2011-02-08 13:14
That's because you're using a very weak test, Juan. Plus you're comparing apples to oranges. Why not download the free AIDA64 trial and run the CPU System Stability Test tool?
Report Comment
# not goodcactus 2011-02-08 23:00
It surprises me that this cooler gets a good wrap from reviewers. As the benchmark shows a highend air cooler performs better than a H70 even with its high speed/loud fans.

A highend aircooler will operate cooler even with a(good)silent 1200RPM fan like the Scythe S-Flex. I know this because i have one and its virtually silent on a Thermalright cooler. I have tested many, many fans and only the best 1200RPM fans are virtually silent, fans spinning at 1600/2000 RPM are just ridiculous.

Why would you put up with noise and pay a lot more for H70 when you can have a cheaper and virtually silent high end cooler. I can only assume some people have never experienced a silent system or know what is possible or have been sucked in by "water" cooling marketting.

And before anyone says "You can run the H70 with 1200RPM fans" the H70 suffers badly with fans at that speed and you can add 10 Degrees to temps.
Report Comment
# Helpful All in one Liquid Cooler ReviewJohn Darcy 2011-02-11 03:48
Thanks for the tips and dremmel tips that are actually tried and tested. I am sometimes fearful of attempting too many cutting operations,or any at all for that matter lest I do irreparable damage to something. It isnt as if I still couldnt , however i enjoy the reviews which actually do make alterations out of the box to make something work better.
I have a gpu which seems to make in non silent even at its factory de tuned super low power usage rates. as soon as it gets beyond 32% it is audible to my old ears and after 34% it is noisy. I have a good aftermarket cooler on one 5870 and it is quieter but not silent. so the notion of a silent system as far as the cpu cooler goes is out. But, there are some good 'quiet' fans which push a fair amount of air enough dramatically reduce my Phenom II 965 in the hot summer. I do not think these liquid all in ones ready for me and my price point as yet. It is good to know how much progress is being made. I have used enough of the well reviewed air cooler/heat sink types and changed fan with good sale silent fans or 100+ cfm represented ones with 'some' noise.
i enjoy the input here on this side of the review as well for the reservoir of experience and info.
your efforts are greatly appreciated here.
Report Comment

Comments have been disabled by the administrator.

Search Benchmark Reviews

Like Benchmark Reviews on FacebookFollow Benchmark Reviews on Twitter