… The IIci uses DRAM for video and maps it to Bank A. Contrary to other Macintosh models, always install the lowest density SIMMs in Bank A for best performance.
As Charlieman suggested, 80ns RAM is needed. If you have no video card in place, onboard video needs Bank A (two right-hand pairs) DRAM to work (so-called 'Vampire Video'). Your total DRAM, depending on your installed System, may then be perilously low. (The IIci can support up to OS 7.6.1 on a 68030 if it has enough RAM, which can be up to 128MB.)
… On-board video support for 12” B&W, 13” RGB, and 15” B&W Portrait monitors …
Various third-party and Apple NuBus video cards can give a wider choice of displays, and also obviate the use of DRAM for video with their on-card VRAM.
When they stripped the IIci maybe they took the ROM jumper at W1. Without it you won't get any video.
Nor anything else, for that matter. That jumper selects between on-board ROM and the ROM slot. There never was a ROM card for the IIci, so the on-board ROM
must be selected. Otherwise the IIci behaves all-same hearthstone. No ROM = no startee. Nix. Nada.
… Parity is generated by the optional Parity Generator Chip (PGC). If you want parity checking you must order the Macintosh IIci configured with the PGC and nine-bit DRAM SIMMs.
The (scarce) parity-checking version of the MLB obliges you to use (9-chip) parity SIMMs (but still 80ns or faster). If there is no Parity Generator Chip to the left of the DRAM slots of Bank B, but only the naked solder-pads, this is not a concern. You can use parity SIMMs in a IIci without a PGC, however, because the ninth chip will be ignored by the System. If you do not have a video card, you could probably use the 4 x 1MB in Bank A and the 4 x 2MB in Bank B (you are fortunate that the IIci is one of the few Macs that will use 512kB and 2MB SIMMs, but not 8MB) to get around Vampire Video effects.
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