HP KAYAK XU800 Each DIMM socket is connected to the SMBus and is described on page

2 System Board

Memory Controller Hub (8240)

Four-DIMM Memory Expansion Card

Four DIMM sockets support SDRAM 100 MHz unbuffered ECC memory modules installed in pairs. Unused DIMM sockets can be left free.

DIMM SOCKET A0

DIMM SOCKET B0

DIMM SOCKET A1
	DIMM SOCKET B1

The MCH supports one Rambus Memory Hub for SDRAM (MRH-S) per connected channel. Each MRH-S allows bridging of a single SDRAM channel on to the main Rambus channel. The MRH-S also translates RDRAM and SDRAM protocols, thus enabling the DIMM Memory Expansion Card to be used on the Rambus channels.

As only one MRH-S is connected to each channel, the MCH operates the MRH-S pair in non-interleaved mode.

		Memory modules must be
	Rambus Channel A	installed in pairs (A0-B0). A0			A1	Upgrades are then
I840
			MRH-S
						installed in pairs
Memory
						(A1-B1).
Controller Hub (MCH)
82840-QP	Rambus Channel B
			MRH-S
				B0	B1

Models are supplied with 128 MB of SDRAM unbuffered ECC main memory. Memory upgrades are available in 64 MB, 128 MB, 256 MB or 512 MB unbuffered 100 MHz ECC SDRAM modules.

MRH-S (Memory Repeater Hub-SDRAM) provides support for two double- sided 100 MHz SDRAM DIMM sockets.

Each DIMM socket is connected to the SMBus and is described on page 57.

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