Now we come down to the board itself. The P5K is based around the same sized ATX board that the P5K-E is based on, and with a similar layout too. The PCB colour however has gone from the bard brow/black colour of the P5K-E to the old light brown we were used to about five years ago. It's nice to see this board colour used again for a change.
ASUS has put a good layout together with only a few gripes. The 24-pin power connector, FDD and COM port connector are located behind the four DDR2 memory slots on the right hand side of the board. The 4-pin power combo connector is located behind the USB/PS/2 rear I/O tower on the left hand top side of the board. The location of the IDE port is the major drama in the middle of the bottom edge and under the expansion slots, a definite problem if you're using a large case and want to use IDE CD drives as you're going to have a mess of IDE cable routing.
While the ICH9R southbridge supports a total of six SATA ports, only four are used on this board from the ICH9R, another little gripe of ours as if it's there why not make full use of it?
Coming to the CPU area the ASUS P5K is extremely clean using solid state capacitors and voltage regulators, though this brings up another issue as only a 3-phase voltage regulation system is used to power the CPU. A heatpipe assembly cools both the CPU voltage regulators and the northbridge, while the P35 northbridge doesn't get anywhere near as hot as the X38 chipset, it still generates a bit of heat and the best way to get rid of it is with the heatpipe design.
The rear I/O ports on the back are proprietary to ASUS, so you need to use the included I/O shield included for ATX cases. One thing ASUS has done is get rid of the PS/2 port for the mouse, in its place are two extra USB ports below the keyboard PS/2 port. A single RCA S/PDIF output makes up the digital audio port. A single eSATA port is also included, eSATA is taking off and it's good to see companies putting these ports on the rear I/O ports even when producing cut-down boards like this.
Now we come down to the expansion slots and the additional controller chips provided. While being a more budget oriented board than the P5K-E there is one major feature that is still included, that being Crossfire support. The P5K has two PCI Express x16 slots, the blue one is routed to the northbridge's 16 lanes and is at full speed all the time, the second slot coloured black runs off the southbridge at x4 speeds. While this isn't the most ideal configuration for a balanced Crossfire setup, it works and if you want to run say two X1950s in Crossfire it's perfect. A single PCI Express x1 slot is the last in the PCI Express slots and three PCI legacy slots finish off the lot.
Additional to this are three major add-on chips. For the Gigabit LAN a single PCI-E Marvell LAN chip uses one of the two spare PCI Express lanes, the second extra lane is used by the JMicron PCI-E SATA/PATA combo chip to give the board its single IDE slot. The eSATA port is also run off one of the two SATA ports from this chip while the last SATA port is routed to an internal SATA port on the left hand side of the board below the audio ports.