The PATA interface was accelerated to ATA/100 and the number of USB connections was doubled to four. For the first time a Fast Ethernet chip (82559) was integrated into the southbridge, depending upon an external PHY chip. An ICH2 could also be used with Intel's 82850 chipset, which, like the 82820 before it, required the use of RDRAM and supported the Pentium 4 CPU. The ICH1 or the new ICH2 (360 pins) could be placed to the side of the 82815. The hastily developed 82815 northbridge, which supported PC-133 SDRAM, became Intel's method to recover in the middle range segment. Customers were not willing to pay the high prices for RDRAM and either bought i810 or i440BX motherboards or changed to the competition. In early 2000 Intel had suffered a significant setback with the i820 northbridge.
Integrated IDE controller for Ultra ATA support.Advanced Configuration and Power Interface (ACPI) Support.PCI Rev 2.2 compliant with support for 33 MHz PCI operations.Thus, the northbridge became the Memory Controller Hub (MCH) or if it had integrated graphics (e.g., Intel 810), the Graphics and Memory Controller Hub (GMCH). Note that, along with the ICH, Intel evolved other uses of the "Hub" terminology. Another design decision was to substitute the rigid North-South axis on the motherboard with a star structure. The Hub Interface was a point-to-point connection between different components on the motherboard.
While its predecessor, the PIIX, was connected to the northbridge through an internal PCI bus with a bandwidth of 133 MB/s, the ICH used a proprietary interface (called by Intel Hub Interface) that linked it to the northbridge through an 8- bit wide, 266 MB/s bus. The first version of the ICH was released in June 1999 along with the Intel 810 northbridge.