Each IDE connector on the board supports two channels per. (Two drives) The combination of drives can vary. For instance, hard drive-cdrom, hard drive-hard drive, cdrom-cdrom, ect....ect.
This is dependent on the number of IDE controllers on the board. Older motherboards had two controllers, allowing a maximum of four IDE devices. Newer motherboards often only have one controller,...
You can only connect as many as the cable has, that is most cables have only two connectors per cable, and most boards have two ports, so usually you can connect 4 drives. Motherboards are cheap, and...
Short answer: Four A much more precise answer: The IDE standard allows for two devices to share a single IDE channel. The most common configuration is for there to be two IDE channels on the...
Most still have 1. Some will still have 2, but they are being phased out. I have not yet seen a PATA-less motherboard, but they are definatley on the way, if not already here. That said, 4, 6 and 8...