Today I want to post about hard drives in ibook G4's and what you SHOULD and SHOULD NOT do. My ibook is the worst model available in mid-2004 with some random addons that make it probably the best one that you could never buy.
1.07 PPC 7447-A
1.25 GB Ram
80 GB HDD
Not combo, super.
Now, if you pick up an ibook akd want to change the HDD out you basically have about 3 options for companies for VERY specific reasons.
You are lucky to have Seagate or HGST. If you have a WD drive you are screwed. If you look at an IDE HDD for a laptop you have the standard pins there for data and power, then 4 off to the side for jumpers. What apple did at some point was make a deal with these companies to put HDD sensors in the drives themselves. With seagate and HGLT the sensors are in the drives in the first place for SMART status, but the WD drives that had the sensors built in were either expensive or for apple only.
Now, back to the jumper wires. When you plug a hard drive into your ibook it will also have the jumpers in that section of the plug to manage HDD modes, states, and sensor use. ALL seagate and HGST drives have these sensors and the machine will boot up fine. Only a couple WD models have them and they die easily. If your ddrive does NOT have these sensors the laptop will freeze on boot, not detect anything (even in the alt boot menu) and then freeze, or not turn on ever. Well.... At least until you take the drive out.
TL;DR don't use WD drives in your ibook. They don't have sensors built in for SMART and the ibook won't know what to do so it won't boot correctly. Use HGST or Seagate.