14 DAY TRIAL // Once upon a time not even the processors really, really needed active cooling but now those days are long gone and it looks like the performance we get from the hardware comes at the price of heating it up. A lot of cooling methods appeared over the years from the simple "put a fan" near the troubling spot to the complex and expensive thermoelectric solutions that can keep the hottest nowadays processor running on ice.
At the same time, hard disk drives need little or no cooling. This was a well-established truth and no average computer user was troubled or lost any sleep thinking about just how hot his hard disk drive really is. Until a few years ago, there was no need for something like a hard disk cooling device. But as producers crammed more and more storage space on disks that did not changed size, heat build up gradually became a problem. Most cooling kits for hard disk drives are using one or two fans to blow cool air over the drive and thus reduce its temperature. NEC and Hitachi found an alternative solution: water-cool your drive.
According to the news site ArsTechnica, the cooling solution implemented by NEC and Hitachi has one more advantage besides cooling a hard drive. As the drive is mostly covered in an enclosure that has water in it, the operating noises are very much reduced, sometimes even as low as 25 decibels. In order to accomplish such a technical feat, NEC and Hitachi actually wrap the hard drive in "noise absorbing material and vibration insulation." This hard disk drive enclosure alongside the low revolving cooling fan and the silent water pump also help keeping the noise level way down.
The cold plates that cover the drive and act like heat absorbers are the best and the newest technology available according to the manufacturers. This pretty much means that they will keep the drives cooler even when the workload is stacking up. As the water-cooling technology is pretty old news and the consumer community is always looking for more silent hardware parts, some may say that NEC and Hitachi were actually trying to make a quieter drive that was heating up really fast and so they decided to water-cool it.