Are you not putting the the hort before the carse? It may very well be that you need to fix this up in order for it to boot. 'Fixing' includes minute board checks and cleaning, as well as necessary replacement of replaceable components.
RAM: identical SIMMs of the same value in groups of four (so as to allow the possibility of 32-bit operation) in each bank, and speed enough (120ns or faster), with the larger value, or only SIMMs, in Bank A. Only in the case of 17MB total do the larger SIMMs go in Bank B.
Failure to pass the splash screen, about signpost five in the boot process, is indicative of specific faults in the HDD (and mebbe SCSI bus). You need a spic'n'span HDD in the long run, and a working boot floppy disk in the short term. Port-switching and chaining the mouse and kb will soon identify faulty ADB ports and peripherals.
Faulty capacitors must be replaced, preferably with tantalum electrolytics for the SMD units. Caps on the power-sweep board need to be in topnotch condition and spec, and the soldered connections of all components renewed. trag offers handy parcels of replacement caps for the MLB. In that connection, the distilled wisdom about repairs and upgrade from many SE/30 parents is available by searching these forums: far more than I can summarize in a single post.
Welcome to the SE/30 Parents & Friends Association.
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