The chipset cooling system consists of two parts. There is a simple low-profile aluminum heatsink on the chipset South Bridge:
The heatsink on the chipset North Bridge is taller and is connected via a heatpipe to another aluminum heatsink covering some of the CPU voltage regulator MOSFET. However, since the voltage regulator doesn’t heat up that much during work, this heatsink may be regarded as part of the chipset North Bridge cooling system.
In fact, this cooling would be sufficient only when the board works close to its nominal mode, when the MCH voltage remains default. Any overclocking experiments on ASUS P5Q Pro require improving the North Bridge cooling by at least adding a fan to it.
This simple cooling system design has in fact a few advantages: the mainboard has enough room for any type of processor cooler. However, I have to stress that there are a few standing out contacts on the reverse side of the PCB right beneath the processor socket, which may cause certain problems if the CPU cooler requires a backplate.
Well, other than those few drawbacks pointed out above, ASUS P5Q Pro boasts very decent PCB layout.
The biggest issue is actually the location of the SATA connectors that might be hard to reach if the second graphics card in the PCI Express x16 slot is long. However, I believe very few people will actually suffer from this drawback.