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Add memory

Shakuhachi's Avatar
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12-21-01, 06:49 AM   #1  
Add memory

I have two old computors (like 486 & 386) and was thinking about taking memory from one and adding to the other. Never done it before and don't know what I'm doing but would like to learn. Any suggestions?


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BSB's Avatar

Join Date: Mar 2001
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12-21-01, 09:19 AM   #2  
you can combine the memory from two old pc's if they both use the same type of mem. and if there is enough open memory slots on the target pc to do this. Both should be using 72 pin simms, and simms must be replaced in 2's. If you take a single mem chip out of one and place in the other, the other will not boot.

Just expose both Mother boards side by side, ground yourself or discharge any static build up and then compare memory chips. If they look the same length, take one out of each machine to be sure and then line em up and see if the slots match up. If the length and contac area looks identical you should be good to go.


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12-22-01, 10:44 AM   #3  
I am not sure but didn't the 386's use 30 pin memory, and the 486 either had 30 pin or 72 pin simms. I am bit rusty on that one, but I do remember some of the older computers used 30 pin memory boards.

Anyway basicly you can use memory from one computer in another provided that they use the same type of memory , and is compatable with the board they are going in,

and they must be installed in matching pairs, if your computer has 4 simm slots, then 2 sets of memory can be added , row 1 - 2 slots can have a matching pair of 2 - 8 megs simms (16 meg total), or 2 - 16meg simms (32 meg total), etc. row 2 which is also a set of 2 simm slots must be a matching set also. You don't have to use both row 1 set and row 2 set, one set can be empty, but if used must be matching pair.

Newer computers uses dimms which do not need matching pairs, and are used 1 at at a time, they still need to be compatable with the motherboard.

Last edited by dkerr; 12-22-01 at 11:53 AM.
Gary Tait's Avatar
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12-23-01, 03:47 AM   #4  
Gary Tait
For 386 SX, memory will be in 30 pin simms, and in pairs.
(if it is an early 386, it could be in DIPs)
For 386 DX, it will be 30 pin, if 4s.

For a 486, it will be 30 pin in 4s, or 72 pins, in singles.
For a Pentium, it will be 72 pin in pairs.

bigmike's Avatar
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12-23-01, 07:38 AM   #5  

And a Partridge in a Pear Tree...

abNORMal's Avatar

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12-26-01, 02:07 AM   #6  
In some of the 386 & 486 machines, there are jumpers on the motherboard which must be set to indicate memory has been added.

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