P5WDG2-WS: The Board
The P5WDG2-WS is member of Asus' "Main Station" line of products, targeted at professional workstations users. As such, this board sports some less common integrated peripherals and features. Some of them are clearly evident just by looking at the board, but others require a bit more of a discerning eye to uncover...
As you can see, the P5WDG2-WS is absolutely packed to the gills. Just about all of the available PCB real estate is taken up by some sort of component or connector. However, even though this is a highly integrated motherboard, the general layout is quite good. All of the connectors and headers are clearly labeled and color coded, and connector placement is good. The 8-pin supplemental power connector is situated at the corner of the board, behind the I/O backplane, and an additional 4-pin Molex and the 24-pin ATX power connectors can be seen just behind the DIMM slots.
Speaking of the DIMM slots, there are positioned in such a way that you can't install or remove RAM when a full-length video card is installed. It seems Asus may have simply run out of real-estate on the P5WDG2-WS and unfortunately had to position the DIMM slots this way.
The P5WDG2-WS is equipped with a pair of PCI Express X16 PEG slots, but because the 975X Express chipset doesn't have 32 PCI Express lanes, only one of the slots has a true x16 electrical connection. By inserting a pair of video cards, the first and second PEG slots' PCI Express lane configuration is automatically changed to a 8x8 configuration. The board also has a pair of PCI-X slots, and another pair of standard PCI 2.2 slots. The PCI-X slots come by way of an Intel 6702PXH bridge chip, which is why you see three heatsinks covering the major chips on the board -- the 975X Northbridge, the ICH7R Southbridge, and the Intel 6702PXH. Another tiny TPM (Trusted Platform Module) slot is incorporated into the P5WDG2-WS as well, which hints to an optional module that'll make this board comply with upcoming DRM standards.
There are also a number of third-party chips and controllers on the P5WDG2-WS. Additional SATA II capabilities are offered by a Marvell 88SE6141 chipset, HD audio by a Realtek ALC882 codec, Firewire 1394a support from a TI TSB43AB22 chipset, and a Marvell 88E8062 PCI Express dual port Gigabit Ethernet controller powers the board's dual RJ-45 LAN jacks.
The P5WDG2-WS has a couple of other interesting features worth mentioning as well. First, the motherboard incorporates Asus' "Stack Cool 2" technology. According to Asus, Stack Cool 2 effectively transfers heat generated by the critical components to the underside of the PCB. And second, the P5WDG2-WS is equipped with an 8-phase power array which is beneficial in a couple of ways. The 8-phase array runs cooler, because the load is spread across more components than in a 6- or 4-phase design, and it also does a better job at keeping input and output current and voltage ripple to a minimum.
The P5WDG2-WS' I/O backplane houses a multitude of connectors, including PS/2 mouse and keyboard ports, coaxial and optical S/PDIF outputs, six more various audio input and output jacks, an IEEE1394a port, a legacy parallel port, dual RJ-45 LAN jacks, and four USB 2.0 ports.