Now that you and Essie Thirty have settled on 5MB as the RAM complement (4 x 1MB plus 4 x 256kB), the best thing to have on hand is another 4 x 1MB (min.), or 4 x 4MB or 4 x 16MB. 30-pin 1MB RAM is virtually throwaway stuff these days, and many of your fellow-soldiers could supply it, but 4 x 4MB (USD10) or 4 x 16MB (USD30) will set you back a little more. Forget about 2MB or 8MB for most Macs (in 30-pin SIMMs). 'Have on hand' because you have some groundwork to do first, as suggested by others: remove the (aluminium) electrolytic capacitors and replace them with tantalum electrolytics after you have washed the MLB thoroughly; resolder all joints on the analogue board and the signal input to the CRT; reset the horizontal and vertical dimensions of the display, and adjust the yoke if need be; make sure that all wiping connectors on the MLB (power in, RAM, ROM, sound out to speaker, SCSI, and FDD) are clean and functional. All of these wrinkles are available in these Forums, in detail.

RAM Bank (4 cards in either bank is obligatory) B, which is inboard of Bank A, can be empty, or contain the cards of smaller value in all cases except 4 x 256kB plus 4 x 4MB (17MB total), which must have the larger cards in Bank B. The SE/30 was the first Compact AIO to be able to support virtual memory, which had probably been set conventionally at 2x physical memory plius 1MB (= 11MB in this case).

Best of fortune in coaxing the Mac through convalescence.

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