1850r RAM

[James Luidl]

Can different size RAM sticks be used in the 1850R, or do they have to be the same size?

[Phillip Williams_2]

Herewith Memory specs for 1850R...

ProLiant 1850R
Configuring System Memory
Standard Memory
Memory Matrix
Intel 82440BX AGPset
Registered SDRAM Features
EDO vs. SDRAM 100MHz Memory DIMMs

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Standard Memory
The memory configuration is identical between the 6/400 and 6/450 models.
All DIMMs must be ECC SDRAM DIMMs.
1 DIMM per Bank, with four maximum DIMM sockets
Standard RAM Maximum RAM Soldered/Socketed Used Slots Empty Slots Total Slots
64 MB 1 GB Socketed -1 x 64 MB DIMM 1 3 4
128 MB 1 GB Socketed -1 x 128 MB DIMM 1 3 4

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Memory Matrix
Models RAM Type Connector Edge Pins Speed Parity
Pentium II - 400/450MHz Processors EDO SDRAM Gold 168 100ns No
Pentium III - 500/550/600MHz Processors EDO SDRAM Gold 168 100ns No

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Intel 82440BX AGPset
The Intel 82440BX AGPset (Accelerated Graphics Port) is used in the following Compaq servers:
ProLiant 1850R
ProLiant 800 350, 350e, 400, and 450MHz
ProLiant 1600 350/400 MHz
Prosignia 740
The 82440BX chipset includes the 82443BX Host Bridge and the 82371EB PIIX4E for the I/O subsystem and allows internal memory bus speeds of up to 100MHz. For maximum performance, it is necessary to use specially designed memory modules called registered SDRAM DIMMs, Synchronous Dynamic Random Access Memory. Registered indicates that incoming address and control signals are latched into a register during the leading or rising edge of a single clock cycle. On the leading edge of the next clock cycle, the signals are presented to the SDRAM components. This mode increases latency by one clock cycle, but results in a reduced bus loading (heavily loaded buses) and signal stability (on faster buses).
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Registered SDRAM Features
Registered SDRAM DIMMs have the following features:
Stable operation -- at 100MHz on heavily loaded buses
Programmable mode register -- to define operating parameters (CAS latency, burst length, etc.)
CAS latency -- 3 or 4 in registered mode, or CAS latency of 2 or 3 in buffered mode
Registered mode -- input signals are registered (buffered) on one clock cycle and passed on to the SDRAM components on the next clock cycle
Buffered mode -- input signals are registered and passed to the SDRAM components on the same clock cycle
A phase-lock loop (PLL) -- PLL circuitry resident on the DIMM provides clocking for the register and SDRAM components. The PLL insures that the DIMM clocking is synchronized with the system clock. Using a PLL reduces loading of the system clock, which can occur when using multiple SDRAM components.
SDRAM power-down capability -- is obtained through the use of a single clock enable line to control all clocking on the DIMM
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EDO vs. SDRAM 100MHz Memory DIMMs

The top DIMM in the illustration above is a registered 100MHz SDRAM DIMM. The bottom DIMM is a standard EDO ECC DIMM.
Hope that helps

Eric

[Phillip Williams_2]

James - the original Compaq memory spec options were 3 different sizes:-
64-MB 100Mhz Registered ECC SDRAM Memory Kit 313614-B21
128-MB 100Mhz Registered ECC SDRAM Memory Kit 313615-B21
256-MB 100Mhz Registered ECC SDRAM Memory Kit 313616-B21


Crucial (I find them very helpful on memory) just quote

256MB SDRAM, PC100

â ¢ CL=2 â ¢ ECC â ¢ Registered

CT145614

$89.99 (USD)

I conclude you can mix, she has 1Gb max over 4 slots, so I'd try as many 256Mb sticks I could find...

R