Below is a short summary of the IBM PS/2 SIMMs that I have found applicable
to PS/2 8580 bus memory adapters.
Size Speed
Option Numbers FRU Number
Manufacturing (Visible) Number
1 MB 85ns.
6450603
90X8624 65X6264
2 MB 85ns.
6450604,92G7196 92F0104
65X6249
68X6127
80ns. 6450608
92F0103 65X5806
4 MB 80ns.
87F9977,92G7199 92F3337
68X6343
70ns. 6450128,92G7200 92F0105
71F7010