The X40 is based on Asetek's fourth-generation all-in-one closed-loop design, which features a copper cold plate that has been improved with denser micro-fins and a new center channel to increase coolant flow. A single NZXT FX-140 PWM fan is in-cluded, and the cooler supports an optional second fan for a push-pull config. It's com-patible with all modern CPU sockets, with the exception of L6A775. but faces a larger compatibility obstacle in that it requires a case with a 14cm fan, such as NZXT's own Phantom 410. The X40 also sports extra-tong 16-inch rubber tubing compared to most other closed-loop systems that use tubes measuring around 12 inches. Accom-panying the larger fan is a wider radiator that offers 36 percent more surface area than smaller 12cm rads.
Like Corsair's H80i that we reviewed last month, the X40 has an LED on top of the pump that you customize to either remain a solid color or to change color depending on temperature, which is slick. We also appreciate that the software to control it comes bundled on disc, whereas Corsair's software requires a download. The soft-ware is easy to use and allows you to adjust fan speeds, but not pump speeds like Cor-sair's equivalent. While it features only two presets, -silent' 11,000rpml and "extreme" (1,700rpml, as opposed to the half-dozen with Corsair's software, you can stilt manu-ally set the fans to run at fixed RPMs and save custom profiles.
Installing the X40 was relatively easy. With our L342011 backplate preinstalled, we began by inserting four screws through the retention ring that allows the water block to be mounted to the CPU socket. The X40 features a similar retention ring to Ther-maltake's Water2.0 Pro, which snaps onto the water block with a retention clip. This mounting process isn't as straightforward as the H80i's simple magnetic mounting bracket, but the X40's manual features ex-cellent illustrations that simplify the instal-lation process. Mounting the radiator and fan to the chassis just required tightening four screws through the back of the case. The last step was to connect the CPU fan and USI3 cables to the mobo headers, and unlike the H80i, all the cables come pre-attached to the water block, and the pump doesn't require additional power [Molex or SATA), making the installation less of a hassle.
In testing, the Kraken X40 was impres-sive, and we were pleasantly surprised to find that the preset silent mode not only lived up to its name, but cooled extremely well, hitting just 67 C under load. This was enough to whoop our Hyper 212 zero-point air cool-er in performance mode by 7 C. and it also bested the 12cm Seidon 120M water cooler running on full blast by 1 C. With the X40's fan cranked to maximum, it gave Corsair's H80i a run for its money even though we had it running in push-pull mode with two fans, which was quite impressive.
While the X40's fan can be mistaken for a small leaf blower at full speed, it fortunately doesn't need to operate at its highest speed to cool well. While the X40 isn't cheap at 100 bones, it's no costlier than its peers and it outper-forms them, making this cooler easy to rec-ommend. If you have a case that supports a 14cm fan, you should definitely release the Kraken!
NZXT Kraken X40 Specifications
Radiator Dimensions (H x D x W): 5.5 6.7 x 1.0 inches
Weight: 1.9 Lbs
Stock Fans: 1x 14cm PWM
Socket Support: LGA 1155/1156/1366/2011; AM2/AM2+/AM3+/FM1
Additional Fan Support: One 14cm (screws included)
View detail specifications
