With AIOs becoming ever more popular it stands to reason that a company such as Corsair should produce a range of coolers that cater for differing performance requirements and budgets. With the H75 Corsair are, in there own words, aiming to produce an AIO for "The masses". Who exactly the masses are remains unclear, but we can surmise that Corsair are aiming at the consumer who wants a high level of performance, in a compact form and at a price that won't make the nose bleed. In price terms the H75 falls between the £5 cheaper H60 and the £10 more expensive H80i. Where will it fall in performance terms? Well that's why we're here.
|Intel||LGA 1156, 1155, 1150, 1366, 2011|
|AMD||AM2, AM3, FM1, FM2|
|Radiator Dimensions||120x152x25mm (LxHxW)|
|Fan Dimensions||120x120x25mm (LxHxW)|
|Fan Speed||2000 RPM (+/- 10%)|
|Static Pressure||2.8mm H2O|
Up Close: Packaging and Contents
The H75 comes in a fairly mature and understated black box, with key features and technical specifications being presented in a multi language format.
Opening the box reveals the instruction booklet and a thin foam padding strip overlying the contents beneath. Corsair have opted for the ever more popular "egg box" cardboard packaging as a means of separating the items internally and preventing them from damaging each other. While the egg box packing might not be as substantial as expanded polystyrene our experience has shown that its well up to the job, and of course is more eco friendly. We also suspect it might be cheaper which is another good reason for Corsair to use it as it ultimately brings the cost to the consumer down.
Lifting out all our eggs in one basket we can dig in and see what goodies lie within.
Aside from the 120mm rad and cold plate with integral pump we get a pair of 120mm SP120L fans, and a multi socket back plate with a sliding location pin as opposed to the more usual notched hole method, we anticipate this will make fitting even easier than usual.
There's also a separate AMD mounting plate (the H75 comes with the intel plate factory mounted but it can easily be removed and swapped). Mounting hardware for the fans and cooler are packed into separate packs to avoid confusion. There's also a Y splitter allowing both fans to be plugged into the same 4 pin header.
Up Close: Overview and contact plate
The H75 utilises a thin radiator which is compatible with 120mm fans. Being only 25mm thick, it is hoped by Corsair that the H75 will have improved compatibility with smaller cases where space is more of an issue. With the continued rise of M-ATX and SFF cases this seem to uss like sound business sense.
The Rad and the cold plate assemble are connected by two runs of matt black anti kink tubing. The tubing is of a medium diameter, and although thin by custom water standards offers an internal diameter that is well up to the job of the short runs and low resistance offered by this AIO set up.
The 300mm lengths of tubing terminate at either end by what appear to be the same sort of simple plastic barb we see on a great many AIOs. At the cold plate end these barbs will rotate approximately 45 degrees in either direction to add greater flexibility.
The pump/contact plate assembly has a good sized copper cold plate which comes complete with a central coating of TIM. In the interests of continuity we will of course be removing this for testing, but otherwise it's a nice thought to have the TIM pre applied. As already mentioned the Contact plate comes with the Intel bracket pre attached, as shown below, but it's the work of seconds to pop it off and attach the supplied AMD bracket.
The Contact plate is essentially a Corsair/Asetec unit, with an internal copper microfin cooling block structure for improved heat transfer. Unlike more flashy (and more expensive) Hydro series units, such as the H80i and the H100i the the H75 does not offer the "i" connectivity, and is instead hooked up by a simple 3 pin fan header.
Up Close: Radiator and Fans
Although the radiator is quoted as being 25mm thick, in reality, as is the case with all rads, owing to the allowances necessary for the mounting bolts to secure the rad without puncturing it, the core of the rad in fact a good 8-10mm thinner. A close examination of the rad reveals that the usual Corsair quality and attention to detail is as present here as it is in any of their products. The paint is applied evenly and there are no bent or mangled fins.
We suspect that if the H75 does well in out torture tests a lot of its success will be down to the choice of fans that Corair have bundled with the unit. No rebadged OEM units here, oh no, these are fully fledged SP120Ls.
Each of the fans has a decent length of unbraided but thankfully black cable and is terminated in a 4 pin PWM header. The fans can be used independently or linked with the supplied splitter cable. Should you be handy with a soldering iron and wish to bling things up a bit you'll be pleased to know that there are holes in the cowling for 5mm LEDs to be fitted.
Unlike most fitting methods that use a back plate with spaced and separated notches for the various sockets, the H75 backplate uses a system whereby the mounting hole is extended on a pin that passes through from back to front making locating the mounting bolts on top of it considerably easier. Each of the four protruding pins is located in a small sliding aperture, causing the pins to quickly find their own seating and position dependant on the CPU socket and therefor mounting hole location. Sounds complicated, but it's actually one of the simplest and most effective methods we've seen yet.
As we're using our socket 2011 test set up we won't actually be using the back plate, so it's onto the next step which is the insertion of the mounting bolts. Separate bolts are supplied for the various socket types and are each easily identified.
The instructions recommend that the radiator is attached to the case before mounting the cold plate. As we're essentially making a radiator sandwich it makes sense to attach the inner most fan first using the supplied bolts. Attaching the rad/fan assembly to the rear of the case while simultaneously passing the bolts though the second fan is quite fiddly but can be done with minimal swearing and pales into insignificance next to the anguish caused by fitting the V8GTS a few weeks back. (the physical scars are healing but the mental scars will always be there). While fitting the rad it's worth finding a safe place for the cold head to dangle as the last thing you want is it swinging about and knocking a cap off your mobo.
With the rad in place we can attach the cold plate. Offering up the assembly to the motherboard, simply slide the grooved mounting holes over the threaded ends of the four mounting bolts. At first you might think you've got something wrong as the holes are much bigger than the pins. All becomes clear as you tighten down the final securing bolts, realising that they are tapered on their under-surface, again to aid them in finding their own centre.
The pump is connected to any 3 pin socket, with the fans being either wired up individually or together via the supplied 4 pin PWM splitter. As this is an AIO, that's all there is to do. The attentive amongst you will notice that we've set up the fans on intake as this is how Corsair instruct it to be done, pointing out as they do Newton's Law of Cooling. Corsair also urge you to consider the fan set up in the rest of your case to ensure that there is sufficient extract for the warm air. In reality the fans can be mounted as an extract set up with only a degree or two of difference being made in the temps. In fact, if you haven't got any ventilation in the roof of your case we would recommend that you set up as extract. For the purposes of our testing we swapped the fans over to extract so as to re create the same conditions that all other AIOs are tested under.
Our trusty Cooler Master "Test Trooper" does somewhat dwarf the H75, but then it's more likely that this cooler will find it's home in a mid tower or given it's diminutive dimensions even a SFF or cube case.
Performance and Testing
We've changed the way we display our graphs in the hope that it makes it easier to gauge how well the item under review has performed in relation to the competition. We've ordered the contents with the best performing cooler at the top, and the worst at the bottom. The cooler under review is highlighted in red within the data set.
The test set up consisted of the following
Intel i7 3960X Stock@ 1.1v (undervolted) 4.0GHz @ 1.25v 4.4GHz @ 1.35v 4.6GHz @ 1.45v Gigabyte X79 UD3 Corsair Vengeance LP Memory Corsair HX850 V2 Corsair Force GT 60GB Coolermaster Storm Trooper.
As usual we'll be testing our coolers at varying levels of overclock and increasing levels of voltage. this in turn of course means increasing levels of heat which the coolers need to dissipate. To begin with we start with the undervolted stock speed. Why undervolted? well if you have things set on "Auto", you may well be using more volts than are actually required to run at the chosen frequency, for example our 3960s will run quite happily at just 1.1volts, solid as a rock, 24/7, and as such we use this as our starting point.
Continuity is very important in testing, and for this reason we keep as many of the potential variables as locked down as possible. We will be using OCCT in Linpack X64, AVX compatible with all logical cores tested and 90% free memory utilised. The test is set up to run automatically with just a few clicks to set it going. A 10 minute idle followed by 30 minutes of testing and a 5 minute cool down is the order of the day and brings the total test time per clock speed to 45 minutes. So as to remove subjectivity in determining whether a CPU has failed, OCCT is set to stop the test and register a fail should the max temp exceed 80 degrees. In testing we noted that if even just one of the cores exceeds 82 degrees OCCT halts the test and a fail is recorded.
The Corsair H75 doesn't come with any low noise adapters or fan speed reducers so the testing was a relatively simple and quick process, simply fit it and fire up the tests.
With a Delta temp of just 24 at stock the H75 makes I into the top third of the charts, being bettered only by beefier AIOs and custom water kits. What's impressive is that the H75 beats the 240mm radiator version of the Eisberg. It also beats the Eisberg 120 and the Corsair H60. These low volt low overclocks are not where the actions at though and aren't tha much of an indicator as to how well a cooler will cope once the volts have been cranked up, so let's wind things up a bit.
Turning now to the 4GHz test we up the voltage to 1.25 volts, this is what is deemed normally as stock volts. Something we are always harping on about on the forums is AUTO does not mean stock volts, and normally if you overclocking with "auto" volts the motherboard will be upping the volts much more than needed if you were to do it manually. By whichever means it happens, upping the volts (especially from our 1.1v undervolt) does have a big impact on temps, with an average increase of 10-15 degrees seen in the results.
At the higher levels of heat generated by the increase in voltage required for the 4.0GHz overclock, fan performance, although still a factor becomes less critical, replaced instead by a coolers ability to conduct the heat up the heat pipes and more crucially the total surface area of the fins enabling convection to the atmosphere. In the case of AIOs and water cooling the surface area of the radiator and the efficiency of the contact plate begin to play more of a factor. Here we see the H75 slip down the charts a little, resting somewhere near half way. It's still getting the better of quite a few of the AIOs in the charts. but with the exception of the Eisberg 240 is being beaten by those with bigger rads and greater surface area. It's also being beaten by the mighty NH-D14, and only jus by the H100.
Upping the volts still further we achieve a stable 4.4GHz overclock at 1.35 Volts. It's here we start to separate the wheat from the chaff, with lesser coolers not able to disperse the increased heat effectively. Again we see a jump of 10 degrees or so from the figures at 4GHz. Both the H100 and the well-respected D14 are creeping into the 70s here, indicating that only the cream of the crop will excel at this level.
This is where we start to separate the men from the boys. So how did the H75 do? Well it's still just about half way in the charts, which remember have been thinned out somewhat as other less able coolers have fallen by the wayside. It's still beating both flavours of Eisberg and a few of the other AIOs, and every single traditional air cooler with the exception of the D14.
Having gotten this far we were really quite hopeful that the H75 might make it into the hallowed 4.6GHz club, but sadly it was not to be with the temps popping over 80 degrees some 15 minutes into the test and triggering an automatic fail.
With the H75 Corsair aim to make a Cooler for the masses. We're not too sure exactly who the masses are to be honest, but we're going to hazard a guess that they're the sort who aren't necessarily looking for the very best with money no object, neither are they looking for the very cheapest, instead they're looking for a well-balanced product, something that will give them reasonable performance, in a compact form to increase compatibility and at a price that won't give them a nose bleed. So have Corsair managed this?
The H75 is certainly a compact unit. The radiator is just 25mm thick, a full 13mm thinner than the more performance centric H80i. This means Corsair have been able to bundle the cooler with a pair of 120mm fans and still keep the overall thickness of the assembly at 75mm. Keeping the thickness of the assembly down of course means you can squeeze it into tighter spaces and smaller cases, and with SFF and compact cube cases increasing in popularity as a result of better performing and spec'd mini-ITX and M-ATX motherboards it's no small wonder that Corsair have chosen to release a product that will cater for these as well as bigger and more traditional Mid towers. The fans supplied with the H75 aren't your standard black OEM jobs either, Corsair have opted to use a pair of SP120L, which at 2000RPM produce a quite reasonable 2.8mm H20 of static pressure and produce 54 CFM of airflow. The fans are wired via 4 pin PWM connections and can be controlled as a pair by using the supplied Y splitter.
The quality of the H75 is as we have come to expect from Corsair. The paint job is decent and evenly applied and there were no bent fins or scratches. The contact plate, which looks to be an Asetek/Corsair unit has a chunky Iron man chest plate look about it. Underneath sits a large circular copper contact plate with copper microfin structure internals to improve efficiency.
Fitting the H75 is a dream, with Corsair seeming to improve on what was already a pretty simple process. In doing away with a notched back plate and replacing it with a slotted raised pin plate and retention bolts that are tapered and so self-seat, Corsair have made it even easier to locate the mounting hardware. This coupled with excellent instructions and a separate and equally attractive mounting plate for AMD users means whatever flavour of chip you're using, you won't have to get irritable over the installation.
Despite generating a rated 34dB(A) at the full 12v we test at, in use the H75 was quieter than a good many of the AIOs we've seen which always seem to have noisy fans, especially when compared to the single fan set up of the H60. The performance of the H75 was also impressive when you consider the thin radiator profile. The unit held its own all the way up to 4.4GHz, seeing off all air coolers apart from the mighty NH-D14. It also managed to get the better of quite a few other AIOs including not just the 120L Eisberg, but the 240mm rad based Eisberg 240L. The H75 didn't make it into the hallowed 4.6GHz club, but then neither did we expect it to.
Looking at the competition in a little more detail let’s start with Corsairs own H60 and H80i. The H75 comes in about £5 more than the H60 and as you would expect outperforms it by 2.5 degrees in the 4.4GHz test, mainly on account of the twin fan set up on the H75. Being £10 cheaper and 13mm thinner than the H80i you'd expect the H75 to not perform as well, and you'd be right as it's a good 7 degrees off the pace. Interestingly the relationship between the prices almost mirrors the price differential between the 3 coolers. If we look at the other coolers in our graphs we can see that the more expensive 240mm rad based systems provide better performance with many of them making it into the 4.6GHz club. Only the NZXT KrakenX40 falls south of the H75 and although this is a slim rad design like the H60, it is based on a 140mm fan so is unlikely to offer the same level of case compatibility as the 140mm fan based H75.
We asked if the H75 was the AIO for the masses that Corsair claim it to be. We guess only time will tell. In the meantime however we suspect that they may be onto something as in the H75, Corsair have indeed produced a cooler that offers good performance enabling a decent overclock. The compact form will enable it to be fitted into many of the SFF and mini cube cases on the market as well as more standard Mid Towers, and the price, well we think for what you're getting for your £68 your nose should remain epistaxis free.
Thanks to Corsair for sending in the H75, you can discuss your thoughts in the OC3D Forums.