To ensure accurate thermal results, we installed the same hardware in each case. The motherboard of choice was the Gigabyte H55M-UD2H which was outfitted with a Core i5 750 cooled using the Cooler Master Hyper TX3. We also stuffed in a Radeon HD 6870, a pair of Western Digital Scorpio Blue 500GB hard drives and OCZ's ZX 850w power supply.
The Silverstone Fortress FT03 amazed us with its thermal performance when at idle. Despite housing the hard drives behind the motherboard tray where appears to be very little airflow, the Fortress FT03 produced the best idle results with our Western Digital drives.
The graphics card performance was also excellent keeping the Radeon HD 6870 at just 34 degrees while the CPU idled at just 24 degrees. Compared to the Lian-Li Mini Q PC-V354, the Fortress FT03 kept the GPU 10 degrees cooler and the CPU one degree cooler.
Although the Antec P180 Mini came close to matching the performance of the Fortress FT03, the fans needed to be set on high, making them significantly louder.
Using Prime95 in conjunction with FurMark, we cranked the heat up on these microATX cases. The FT03 saw the graphics card temperature reach 79 degrees and the processor peaked at 47 degrees -- much hotter than the case's idle temps, but still better than its rivals.
The Mini Q PC-V354 saw the CPU temperature rise 15 degrees above the Fortress FT03, while the GPU was 7 degrees hotter. Antec's case fared better but it was still hotter than the FT03. NZXT's Vulcan performed the worst, ranking a notch below the Mini Q.