Performance
Fractal has made numerous usability improvements, and there's now a greater scope for end-user upgrades, but the out-the-box proposition is similar. This is still a sound-proofed case outfitted with an intake and an exhaust, so it's no surprise to find that CPU cooling performance is in the same ballpark as the ageing Define R4. The R5's default setup doesn't deliver spectacular results, but our overclocked CPU is running well within its limits.
GPU temperature is also close to that of the original. Keeping under 80ºC in a quiet case with dual Radeon HD 7950s is a reasonable showing, though with extreme graphics setups we'd be inclined to make use of the optional side fan mount.
Here's where the Define Series tends to come up trumps. It is very quiet. Switch the fan controller to low and the test platform is barely audible when idle. Noise levels increase when gaming - the dual Radeon HD 7950s are to thank for that - but with the right components, a Define R5 could be made to run very quietly at all times. We're thinking a couple of SSDs, perhaps a GTX 970 with 0dB fan technology and an ultra-quiet air cooler. That would be our kind of build.