i was going by everymac:

Display Support: Single Display* Resolution Support: 640x480*Details: *Onboard video is capable of supporting a maximum resolution of 640x480. If the optional NuBus adapter card is installed, a second video card can be installed to support a second display. The NuBus adapter also provides a 68882 FPU.

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but i guess there is more tidbits at LEM:

http://lowendmac.com/1990/mac-iisi/

my current Mac to VGA adaptor is configured for 640x870, but its in only blue:

so if lem says this:

640 x 870) at 4-bits

Click to expand...

then i guess its nativly capable, (maybe)

not sure why every mac doesn't mention it… and as to why i tried like every switch config and this(all blue in first post) and 640x480 (normal looking) 256 colors is all i can seem to get outta it.

maybe everymac didn't mention it because it doesn't actually work due to screwd up looking color as in what i have here.