Also check the memory jumper on the accelerator: with it wrongly set the memory will never show up.
And Amiga1260 is right: the Apollo is a b!tch regarding which SIMM sticks it will like. EDO is a guessing game, most Fast Page units will work, but they where only made up to 32MB (which are hard to find).
Oh, the Apollo will only accept up to 32Mb SIMM (or 64Mb with the second SIMM socket soldered).
