OK blue_wolf as said by my colleagues above. And:

1. Your floppy has a separate connector.............you cannot get that wrong without using a large hammer

2. The MoBo connections are obvious as well (please check fourdc's comments there)

3. You should then have 3 or 4 Molex connectors (vaguely rectangular, about an inch square with 4 female connection points). These have no particularly significant order, but my feeling is that if you have two HDDs you should allocate them an individual connection. If you have to split one, then put the CD/DVD drives on that one.

It all depends on how you use your computer. Like if you do a lot of direct CD/DVD copying, I would share the read drive with the least used HDD (on the grounds that the drive doing the burning is probably getting more stress). But that is probably just my personal paranoia..............I have not come across anything authoritative to support it.