Noise, Additional Testing and Conclusion

This content was originally featured on and has been converted to PC Perspective’s website. Some color changes and flaws may appear.

When I first set the system up and turned it on I was very surprised at how noisy the HydroCool 200 external cooling unit seemed to be. The source of the noise wasn’t the fan in Turbo mode but appeared to be a very loud hum coming from the pump. I quickly discovered the Plexiglas side panel was actually resonating. After applying a thin strip of foam weather-stripping to the metal frame beside the pump – the noise disappeared!

I took sound pressure level readings of the HydroCool 200 external cooling unit running in both Whisper and Turbo modes. Readings were taken 3’ from the front of the unit in an otherwise quiet room (approximately 30 dBA background).

Corsair HydroCool 200 Review - Cases and Cooling 30

While running in Whisper mode, the HydroCool 200 was relatively quiet and might not be heard over a computer’s normal PSU, HDDs and case fans. In Turbo mode the noise was definitely more noticeable. Considering the minimal impact Turbo mode has on temperatures, I’m quite happy to leave the system running in Whisper mode most of the time.

Additional Testing

Initially I had planned to tear the little HydroCool 200 system apart and remove all those obvious flow restrictions! But since testing the system and seeing how well it performs at very low flow rates, I no longer see much point. As long as the HydroCool waterblock is the primary flow limiting component, then the other components have much less affect.

Corsair HydroCool 200 Review - Cases and Cooling 31

I was still curious to see how the HydroCool waterblock would respond to a higher inlet pressure. To perform this test I replaced the HydroCool 200 external cooling unit with an Iwaki MD-15R pump and D-Tek heater core with two shrouded 120 mm fans in push/pull. This setup produced 3.5 PSI going into the waterblock and resulted in 3~4ºC lower temperatures.

Corsair HydroCool 200 Review - Cases and Cooling 32

Pretty impressive numbers for the little Delphi waterblock! The micro-channel design produces significant backpressure, that when overcome with higher pressure, results in greater flow and reduced temperatures. From the previously shown waterblock flow curve we can estimate the total system flow with the Iwaki pump is approaching 50 GPH. This corresponds well with theory, which states that pressure must increase by a factor of 4X to double flow rate.


The HydroCool 200 external liquid cooling system is an excellent first effort by Corsair Memory and Delphi Thermal Systems. The system is well-made using quality components and comes with everything you need (except distilled water) to setup a PC water-cooling system.

The real strengths of the HydroCool 200 system are convenience and ease of setup. If you are looking for a solid water-cooling kit that is both portable and easy to install, I highly recommend the HydroCool 200. Performance is above average and includes some very nice features like portability, a temperature display and audible alarm/shutdown controls that most custom-built water-cooling systems will not have.

The 3-lug waterblock mounting clip was very easy to use and because of its design holds the block securely in place, centered over the CPU.

In the future I would like to see Corsair/Delphi add an air intake filter to the external cooling unit and I hope they make the waterblock available for purchase separately.

The HydroCool 200 liquid cooling unit is a good example of what can be done with low flow rates. It just goes to show you don’t have to have 300 GPH and a 1/2” system to work effectively as long as the key components are optimized for low flow.

Thanks to Corsair for sending us this unit to review! I would also like to acknowledge that some of my initial impressions were wrong (like that’s never happened before… 🙂 and the gear-heads at Delphi really do seem to know what they are doing. Good job, guys!

You can pick up the Corsair Hydrocool at both and

« PreviousNext »