Reference Board Layout and Design
This content was originally featured on Amdmb.com and has been converted to PC Perspective’s website. Some color changes and flaws may appear.As with all reference boards, the designs are simply not very intriguing and they don’t offer all the available options that the chipset may feature. The NVIDIA board is no exception.
On this picture, you will see the single AGP slot, compatible with 4x cards, two PCI slots and a single ACR slot. The ACR slot is physically just a normal PCI slot, turned 180 degrees. This ACR slot comes into play later with the MCP south bridge.
Also notice that neither the IGP nor the MCP having any kind of cooling on them. During testing, neither chipset got hot enough to the touch that I for-see the need for active cooling, but passive cooling (i.e.: a heatsink) may be in order for any kind of overclocking potential on retail boards.
The reference board I was sent uses the nForce 420 chipset, which, unlike the nForce 220 chipset, has the 128-bit memory architecture option. In order to take advantage of the extra memory channel and get the boost in performance, it is necessary to have one DIMM in the first slot and at least one DIMM in the second or third slot. If you leave the 2nd and 3rd slots empty, the chipset will resort to its 64-bit mode and thus your extra cost of the 420 version of the chipset was wasted.
If you notice the external connections at the top of board, you will see that while there is the header for the on-board video and standard audio, there aren’t headers for the network connection, modem or digital audio. All of those features were include in the ACP riser card, pictured below. Some motherboard manufacturers may choose to add the options to the headers where the PS/2 and USB are, hopefully all will at least include the ACP riser card so that users can take advantage of all the features.
The riser card itself is fairly simple, as it merely acts as the headers for the features that are located on the MCP south bridge.