all installed and ready for testing!

First the system specs:
- AOpen: AMD XP1500+@1333 (standard)
Fans present : 1 intake, 2 outtake + PSUfan

- Chieftec: AMD XP1500+@1500@1.85V (XP1800+)
Fans present : 2 intake, 2 outtake + PSUfan

- CPU temps are @ full load
- CPUfan: Enermax@full speed (blowing on the HeatSink (=ThermalTake 6CU))
- Room temp was 22°C during all tests.

As you can see by yourself, all the components are much cooler, even when I overclocked the CPU!
How come?
1) 2 outtake fans right above the PCI and right next to the CPU => pulling a lot of warm air out of the case
2) The PSU in the Aopen tower hangs right above the motherboard, so there isn't a lot of space left for the air to move to the upper part of the tower (to the 2 fans). IDE and other cables block the airflow even more.
Also very nice is the 340W PSU included in the box. Aopen delivers a 300W PSU with their tower. The PSUfan of the Aopen PSU has only 2 speeds: slow (low casetemp) and fast (high casetemp). Once it starts turning fast, it won't go back to the slow setting, even when the system had cooled down enough. The Chieftec PSUfan has a variable turning speed that will turn slower again when the system has cooled down.
The 80mm fan holes made by the manufacturers are also very different: the Aopen holes are much smaller, causing less airflow and more noise. With this case, we are almost forced to dremel out the holes above the PSU. The Chieftec setup with 4+1 fans was much quieter then the Aopen setup with 3+1 fans… This is very interesting for people who don't want to hear a plane right next to them while working.
Oh yea, there is something that I want to remark: above the PSU (in the Chieftec tower) a big 92mm hole was made. This is very nice, of course, but I don't understand why Chieftec didn't make a 120mm hole, since there is plenty of space left…