Big Cooling For Little PCs: Corsair H5 SF All In One Liquid CPU Cooler Review

by Ryan Perry on September 1, 2016 in Cooling

Cooling options for those building or upgrading an itty bitty mini-ITX system are few and far between, and even less so if liquid cooling is a must. Fear not small form factor lovers, Corsair is here to save the day with the H5 SF, the mightiest of all mini all-in-one liquid coolers, so read on to see if it can keep up with today’s pint sized powerhouses.

Page 2 – Corsair H5 SF Testing

Performance Testing

All of our testing is performed under controlled conditions to ensure accurate and repeatable results. The test system is kept in a near steady 20°C ambient environment with readings taken before and after testing with a standard room thermometer. The Intel Extreme Tuning Utility (XTU) is used for monitoring and recording temperatures throughout the test process.

Stock CPU settings were obtained by reverting to the default settings via the motherboard BIOS, while a moderate stable overclocked frequency of 4.2GHz was reached by simply setting the multiplier to 40, leaving the bus at 100mhz, and increasing the core voltage to 1.22V.

A fresh, fully updated installation of Windows 10 is allowed to sit idle for 10 minutes after startup to ensure all services are loaded before recording idle CPU temperatures. CPU load temperatures are generated by performing a 20 minute run of the XTU CPU Stress Test to generate as much heat as possible.

Chassis Test System
ProcessorIntel Core i5 4690K 3.5Ghz, Overclocked to 4.2GHz/1.22V VCore
MotherboardMSI Z79I GAMING AC
MemoryCorsair Vengeance LP 2 x 8GB DDR3 @ 1866mhz
GraphicsMSI 280X 3G GAMING
StorageCorsair Force LX 256GB SSD
Power SupplyCorsair CX600M
ChassisCorsair Obsidian 250D
CPU CoolingCorsair H5 SF all-in-one liquid cooler
GPU CoolingStock
OSWindows 10 64-Bit
Corsair H5 SF CPU Cooler Temps
Stock CPU Idle36ºC
Stock CPU Load60ºC
OC CPU Idle40ºC
OC CPU Load79ºC

Once the Corsair H5 SF was properly seated, temperatures during overclocked load testing stayed well within the thermal limits specified by Intel, which was a huge relief.  We also found that there was no difference between the numbers when the H5 was installed in the 250D or the 380T, which could be attributed in part to the foam gasket that runs around the exhaust opening.

The entire opening was covered by the dual 80mm fan mounts on the 250D, but an area of each corner of the exhaust port in the 380T was blocked by the narrower single 120mm fan mount.   The gasket meant that what little warm air could have escaped back into the chassis wasn’t able to, meaning temperatures stayed constant between the two chassis.

While the temperature results are great given the compact size of the chassis and the cooler itself, we weren’t fond of the extra noise generated by the GPU-style fan compared to other Hydro-series coolers that use a more traditional case fan.

The short maximum RPM period that seems to go hand-in-hand with all-in-one liquid coolers when a system is powered on is no longer present, but during normal operation the increase in fan speed is clearly audible as the processor is taxed in short bursts.  A faint whining noise can be heard when CPU usage reaches even 10%, which can get very annoying for someone trying to concentrate on, oh I don’t know.  Writing a tech review?

Those who wear headphone or have music playing most of the time may not notice this, but my simple mind needs silence while I work, and I wasn’t getting it with the H5 due to the fan spinning up every 45 to 60 seconds or so.

Final Thoughts

It’s no secret among the TG staff that I like my rigs small.  In fact my constant gushing over smaller hardware is one of the reasons why we’ve decided to move forward with building a small form factor rig designed specifically to test mini-ITX and micro-ATX chassis seeing how they are more popular now than ever before, so stay tuned for that.  Thankfully we were lucky enough to have a rig with which to test the Corsair H5 SF, because it certainly has all the makings of a winner.

It’s easy to install, compact enough to fit into most chassis assuming the proper amount of home work is done first, and it’s capable of keeping mild to medium overclocked chips cool.  Make no mistake, this isn’t an H80 or H100, but it is a solid, all around cooling solution for those who want more brawn than a low profile air cooler is likely to afford.  Speaking of the H100, we had intended to see how the H100i compared to the H5, however it decided to give up the ghost just before we began testing.  R.I.P. good buddy.

The major problem that we found with the H5 is the extra noise generated by the different type of fan.  I’ve tested many Corsair Hydro coolers and they have all managed to stay whisper quiet while navigating around the OS, opening Photoshop, viewing pictures, and performing other basic tasks.

The H5 however, continuously spun up and down, making a faint whining noise each time that simply became too much to overlook.  Don’t get me wrong, it isn’t a loud noise, but it is audible and frequent enough to make it standout among the usual noise made by other case fans, a second system about 4 feet away, and the NAS sitting beside me.

Corsair H5 SF - Promo Shot

Also it would have been nice if a fan splitter cable was included seeing how most mini-ITX motherboards only have a couple of fan headers.  Thankfully I was able to scrounge one out of my box of odds and ends, but the average user may not be so lucky and will need to tack on a few extra bucks to the total cost of their build or upgrade.  It’s either that or say goodbye to any additional case fans.

Speaking of cost, the H5 comes in at a reasonable $75 USD at most major online retailers.  That might seem like a lot compared to some air coolers, but with mini-ITX systems your options are limited to begin with.  We feel that by spending a little extra on the H5, your chip will stay cooler since we’ve proven time and time again that the majority of air coolers, whether compact or not, simply can’t hang with all-in-one liquid coolers, and the ones that can aren’t likely to fit in a mini-ITX chassis anyway.  There’s also the fact that all warm air is exhausted from the system, whereas air coolers leave some of it swirling inside the chassis, resulting in higher overall temperatures.

All in all, the Corsair H5 SF is a solid performer, but the noise is just enough to keep us from awarding it an Editor’s Choice Award.  This might not make a difference to some, and it’s those people who will fall in love this cooler, but for those who absolutely need the quietest rig going, this simply won’t do the trick.


  • Compact design ensures greater compatibility with chassis.
  • New fan and radiator is capable of cooling even overclocked processors.
  • A solid price to performance ratio.


  • Far from the quietest solution.
  • Small amount of room to run cables under the radiator.
  • No fan splitter included.

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