I don't know what the config of the iMac is, but if it has the HD and CD on
the same IDE interface, and both are slave/master, then it would
behave something like this.

In theory, you should be able to boot to CD (C key pressed) with no
hard drive in the machine.

Did you check the jumpers on the new HD vs. old HD?

-dgl-


Bruno wrote:
>    I have changed my Imac 350 mhz 6.4 gig hard drive  with a new maxtor 30 gig 100hz IDE hard disk. On startup, even with the install CD in place and C  key pressed, it doesn't boot into the system 9 to partition the new hard disk. I  get an icon with a flashing question mark. If I enter open firmware and try to give it boot  cd, the answer is can't find HD:,\tbxi ; the same answer happens if I try a boot  floppy command, Original IDE disk was a 33 hz one; from a website I  read that somebody replaced it with a 66 hz ide without problems, only it worked  at 33 hz, so I inferred that my new 100 hz should have worked at 33. What can I  do ? Please help me.   Best regards   Bruno