Performance Analysis

With panels that clearly restrict airflow, thick insulating material on much of the inside, and only two low-RPM fans providing airflow, the relatively poor thermal performance is to be expected. Even at full whack, the CPU and GPU delta T results of 58°C and 54°C respectively are rather far down the charts. At medium speed these only warm up by 1°C each, which is a reasonable trade off, but at low speed the overclocked hardware really gets toasty, with our GPU reaching the joint highest delta T from a case so far, suggesting that at this level the front fan is pretty ineffective. The CPU isn’t quite as bad, but we’d probably steer clear of the low speed setting unless your hardware is especially low power and/or well cooled.

The upside of the warm temperatures is low noise, and not just as a result of the noticeably quiet fans. The chassis itself is clearly very good at containing system noise, so if this is a priority you’ll likely be very pleased.

We do think Be Quiet! has gone a little too far in keeping noise down, though. Given that it has a fan controller, it would be better to see a wider range of thermal performance between the top and bottom speed (especially at the top end), which could’ve been achieved by allowing the fans to run faster.

Conclusion

The airflow limitations of the Be Quiet! Silent Base 601 are obvious from the thermal performance, and this also means that it isn’t a great all-rounder and thus will never be the go-to mid-tower in this fairly premium price bracket. That said, there are many users that value low noise and prioritise it when putting together a build, and for these the Silent Base 601 should definitely make the shortlist. After all, you can make up the difference by buying oversized CPU and GPU coolers that the chassis is easily capable of accommodating. The attention to detail throughout is also admirable – Be Quiet! makes lots of design choices geared towards the goal of quelling noise, which we appreciate.

Also on its side are good build quality and enviable ease of use, both outside and in. The internals are also flexible in permitting builds with liquid cooling or copious amounts of storage. The absence of USB Type-C is a clear oversight, and we think the PSU shroud could be better designed, but overall this is a decent outcome for Be Quiet! The Fractal Design Define R6 is the better all-rounder, but if you’re putting together a build where low-noise is the number one priority, then provided you also invest in good coolers for your core hardware, the Silent Base 601 comes recommended.