Am i missing something here? I'm not so familar with ROM's...

From : http://home.earthlink.net/~gamba2/os8_se30.html

IC part numbers:342S0654-A

342S0653-A

342S0652-A

342S0651-A

IC package: PLCC-32

ROM base: 27C512

ROM type: OTP EPROM ( 64K X 8 )

Click to expand...

These do match by codes (memory modules).

The ROM i have also reads - 820-0244-01 and ASSY 630-4333 and silk printing "512K ROM SIMM-32" - Apple Computer © 1988

So this is an 512k ROM for SE/30? How come so, it shipped with 256k ROM? Can't be so. Must be IIx or IIcx etc??