To ensure accurate thermal results, we installed the same hardware in each case in virtually the same way. Components included the Asrock Fatal1ty 990FX Professional, Phenom II X6 1100T, Prolimatech Megahalems in passive mode (i.e. no fan actively dispelling heat) and the Inno3D GeForce GTX 580 OC.
Normally, we also install half a dozen WD Scorpio Blue 500GB hard drives, and OCZ's ZX 1000w power supply. There are two problems with that configuration in the Silverstone Fortress FT05: it supports only two 3.5" drives and with OCZ's ZX 1000w PSU the enclosure's 3.5" drive cage has to be removed.
Therefore, we installed a shorter power supply and went with just two WD Scorpio Blue 500GB 3.5" hard drives.
Back when we tested the Fortress FT04, its CPU results were poor while the case offered excellent GPU and hard drive cooling. This is due to our testing methodology which sees the CPU passively cooled so it's the case's job to move air over the chip's heatsink.
This was a problem for the FT04 as the heatsink was completely blocked by hard drives, resulting in an idle CPU temperature of 47 degrees. The FT05 works far better, keeping the CPU at just 24 degrees at idle when using the low fan setting. The GPU also ran very cool at just 35 degrees, again with the lowest fan setting.
Turning the fans up to medium and high reduced temperatures by a few more degrees, providing some of our best results.
Placing the entire system under load saw the Fortress FT05 deliver remarkable results with its low-speed fan setting. The GPU hit just 76 degrees while the CPU maxed out at 70 degrees -- comparable results to the Cooler Master HAF X. Spinning the fans faster on medium and high produced our best GPU and CPU results to date.