New I/O Controller Hub (ICH2)
Just like there were two versions of the i810 chipset, each with a different I/O Controller Hub, there are also two versions of the i815 chipset, again, each with a different I/O Controller Hub. We have been talking about the i815 that uses the conventional ICH1 that we’re used to and that has been present on pretty much all i810E and 820 motherboards. The i815E chipset, just like the i820, features the new 802BA ICH2 that adds Ultra ATA 100 support as well as an additional USB 1.1 controller (it does not support USB 2.0), which increases the total numbers of supported USB ports from 2 up to 4.
A CNR Slot
One of the biggest features ICH2 supports is its integrated 82559 network core, which allows for 10/100 Ethernet or HomePNA ports to be placed on the motherboard at a relatively low cost since the core is integrated into the ICH2. If a motherboard manufacturer doesn’t want to place the ports on the motherboard itself, they can take advantage of another supported feature of the ICH2, which is Intel’s Communication and Network Riser slot, otherwise known as CNR.
You can consider CNR to be the replacement for AMR as it can be used with modified AMR cards for the same purpose (CNR is not pin compatible with AMR), but at the same time it allows you to take advantage of the integrated 82559 network core without forcing the motherboard manufacturer to place an Ethernet/HomePNA connector on the motherboard itself.
Unlike AMR, CNR could end up becoming a very useful feature for AnandTech readers – if CNR cards become readily available online.
Currently, most i815 motherboards will be using the ICH1 chip, but by sometime in the second half of this year, Intel expects the ICH2 to be in over half of all of the i815 motherboards that are shipping.