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The optional DIMMCHECK 168P PRO (p/n INN-8484-10) is a universal 168P DIMM adapter which tests most buffered and unbuffered 3.3V or 5V standard DRAM DIMMs. This adapter benefits most volume test requirements as it features a quality YAMAICHI test socket with easy insertion and removal.

It enables SIMCHECK II or SIMCHECK PLUS to test 168-pin DIMM (84x2 pin Dual-Inline-Memory-Module) modules with basic configurations of 64, 72, and 80 bits. Based on JEDEC standard 21-C, the x72 DIMM can be wired as PARITY or ECC (Error Correction Code) types. The x80 DIMM comes ECC type only. The DIMM module has an internal architecture similar to the 72-pin SIMM module, but to achieve a wider bus, the number of -CASx control lines has been doubled from four (-CAS0,1,2,3) to eight (-CAS0,1,2,3,4,5,6,7). Also, two Write Enable control lines (-WE0 and -WE2) and two Output Enable (-OE0 and -OE2) have been added. This arrangement allows for one-bank (e.g. 1Mx72, 4Mx64, 16Mx80) or two-bank (e.g. 2Mx64, 8Mx72) embodiments. Special A0 and B0 address lines (for the first multiplexed address line) have been implemented within the DIMM 168 pin standard for optimized bank interleaving operation.

The DIMMCHECK 168P PRO is conveniently installed in the 90-pin expansion slot of SIMCHECK II or the 40-BIT PORT expansion slot, and is automatically recognized. All memory cells are fully tested.

IMPORTANT NOTE: The DIMMCHECK 168P PRO cannot support the new Synchronous DRAM DIMMs. Please refer to the Sync DIMMCHECK 168.


This tester connects to SIMCHECK II via the 90-pin expansion slot located above its 72-pin socket. It can also be used with SIMCHECK PLUS by connecting the tester to the 40-BIT PORT. Plug the adapter into the 40-BIT EXPANSION PORT of SIMCHECK II or the 40-BIT PORT only when power is turned OFF.

CAUTION: Failure to turn power OFF when connecting or disconnecting the DIMMCHECK 168P PRO may result in damage to the two PAL chips of the DIMMCHECK 168P PRO!

HANDLING THE 168-PIN DIMM: The 168-pin DIMM is a delicate device which warrants great care in handling. The edge connector portion (which is inserted into DIMMCHECK's socket) has two key notches which are keying the device for the right socket. The first key is placed between contacts 10 and 11 (or between contacts 94 and 95 when viewed from the back of the module) and it determines if the unit is a standard buffered or unbuffered DRAM, or if it is Synchronous DRAM. DIMMCHECK 168P supports only standard DRAM. The second key is placed between contact 40 and 41 (contact 124 to 125 in the back) and is keyed for the voltage. DIMMCHECK 168P PRO will test both the 5.0V DIMM and the 3.3V DIMM, buffered or unbuffered versions.

INSERTION: The socket has two ejectors that need to be opened prior to insertion. Carefully insert the DIMM into the socket, pushing it evenly along its top. When the DIMM is properly inserted, the ejectors will snap onto the semi-circular notches on each sides of the modules.

REMOVAL: The DIMM is easily released from the socket by pulling both ejectors sideways.

NOTE: DIMM insertion and removal should be done only during STANDBY mode.

Turn SIMCHECK II or SIMCHECK ON once the DIMMCHECK 168P PRO is installed in the 90-pin expansion slot and insert the first DIMM module. THERE IS NO NEED TO SETUP SIMCHECK II or SIMCHECK, as both units will automatically recognize this tester. After the first DIMM has been tested and the LCD returns to the STANDBY mode, the presence of the DIMMCHECK 168P PRO is recognized.

Required SIMCHECK EPROM Version: 2.50 or above
Required SIMCHECK II Firmware Version: 1.23 or above

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