UDB Memory Configurations

Cache Configuration Troubleshooting	UDB MEMORY CONFIGURATIONS The Universal Desktop Box uses industry standard 70ns JEDEC 72pin, 36bit SIMM modules. EDO, 32bit, and SIMM modules that emulate parity cannot be used as the Alpha processor utilizes a 72bit memory bus, consisting of 64 data bits plus 8 bits for ECC. SIMM modules must be installed in pairs of identical size and preferably from the same manufacturer The 233MHz VX41 and VX42 variants of the UDB can accommodate special Digital 12MB SIMM modules, part number 54-23627-AA. These 12MB SIMM modules can only be used in slots 0 and 1 if they are to be fully recognized. Should they be used in slots 2 and 3 they will appear as only 8MB modules. Due to the compact design of the Universal Desktop Box only SIMM modules that meet the JEDEC standard height of 1.5 inches may be used, most Digital 64 MB SIMM modules exceed this height and cannot be used.
	SLOT 0	SLOT 1	SLOT 2	SLOT 3	TOTAL
	8 MB	8 MB	Unused	Unused	16MB
	4 MB	4 MB	8 MB	8 MB	24 MB
	12 MB	12 MB	Unused	Unused	24 MB
	8 MB	8 MB	8 MB	8 MB	32 MB
	16 MB	16 MB	Unused	Unused	32 MB
	4 MB	4 MB	16 MB	16 MB	40 MB
	12 MB	12 MB	8 MB	8 MB	40 MB
	8 MB	8 MB	16 MB	16 MB	48 MB
	12 MB	12 MB	16 MB	16 MB	56 MB
	16 MB	16 MB	16 MB	16 MB	64 MB
	32 MB	32 MB	Unused	Unused	64 MB
	4 MB	4 MB	32 MB	32 MB	72 MB
	8 MB	8 MB	32 MB	32 MB	80 MB
	12 MB	12 MB	32 MB	32 MB	88 MB
	16 MB	16 MB	32 MB	32 MB	96 MB
	32 MB	32 MB	32 MB	32 MB	128 MB
	64 MB	64 MB	Unused	Unused	128 MB
	4 MB	4 MB	64 MB	64 MB	136 MB
	8 MB	8 MB	64 MB	64 MB	144 MB
	12 MB	12 MB	64 MB	64 MB	152 MB
	16 MB	16 MB	64 MB	64 MB	160 MB
	32 MB	32 MB	64 MB	64 MB	192 MB
	64 MB	64 MB	64 MB	64 MB	256 MB

UDB MEMORY CONFIGURATIONS

SLOT 0

SLOT 1

SLOT 2

SLOT 3

TOTAL