An assembled system case is tested at a constant ambient temperature of 23°C maintained by an air conditioner. As we assume that most users prefer low-noise computers, we set the speed of the CPU and system fans (those connected to the mainboard’s 3-pin connectors) into Silent mode (the quietest mode in the mainboard’s BIOS). If the system case has its own speed controller, we switch it to minimum speed, too. We do not change the default configuration of airflows determined by system case design.
The following components are installed into the system case:
- ASUS P5E mainboard
- Core 2 Duo E6850 processor
- Zalman CNPS9500 AT cooler
- Four hard disk drives Western Digital Raptor WD740GD
- HIS IceQ3 Radeon HD 3870 graphics card
- 2GB DDR2-800 SDRAM Patriot PDC24G6400LLK
- Microsoft Windows XP Professional SP2
- Seasonic M12D SS-850EM power supply (850 W)
The CPU temperature is read with the ASUS PC Probe utility included with the mainboard. The temperature of the HDDs is measured with HDD Thermometer. The graphics card’s temperature is reported by its control panel. The speed of the fans is measured with an optical tachometer Velleman DTO2234. There are the following test modes:
- IOMeter (IOMeter’s Access Time test running on all the HDDs to load them fully)
- Prime95 (Prime95 running in In-Place Large FFTs mode to load both CPU cores fully)
- 3DMark06 (3DMark06 running at 1280x1024 with maximum graphics quality settings)
Every temperature is read after the system has worked for half an hour in the current test mode.
The following table shows the temperatures of the components if the system is assembled without an enclosure (“open testbed”).
The noise level is evaluated subjectively.
First, let’s check out the performance of each system case and see how the cooling of hard disk drives depends on their position. We will also discuss the noise factor.
The HDDs are numbered from top to bottom.
Cooler Master USP 100 at min fan speed
The Cooler Master has some problems at the minimum speed of its single fan. It finds it hard to cool the HDDs installed close to each other. The graphics card has a rather high temperature, too. The system case is quiet in this mode, though.
Cooler Master USP 100 at max fan speed
When the speed is increased to maximum, the fan becomes noisy. The plastic honeycomb and the decorative metallic grid of the fan seem to contribute to that noise. On the other hand, we see the temperature of each problem component go down. They have obviously lacked air flow previously.
The Foxconn doesn’t set any records but performs well enough overall, even though we might expect better results considering how many fans it has. On the other hand, its noisiness is quite acceptable. Although not silent, the system case is quiet enough not to irritate most users. We did not like that the case would produce additional sounds at high HDD load. It obviously lacked rigidity.
The GMC is cool and quiet. We could hardly doubt its cooling performance beforehand considering how many fans it has but we are very pleased with its quietness (although users who prefer absolutely silent computers will find ways to improve it even more). 250mm fans are not always so calm.
Zalman Z7 Plus at min fan speed
The Zalman is good at the minimum speed of its fan. It cools the components well and doesn’t produce too much noise at that. The only problem is about the fourth HDD which obviously lacks fresh air.
Zalman Z7 Plus at max fan speed
Well, the increased speed of the fan lowers the temperature of the components somewhat but also makes this system case much noisier. The fans begin to produce a distinct hum. So, we guess you should use these fans in their low-speed mode as far as possible (unless you install some monstrous graphics card whose cooler is going to shout down a few such system cases put together).