Ok, an IDE cable, such as runs to a hard drive or optical drive, measures about 2" wide. If you were to count the little holes in the connector for this cable it would have 2 rows of 20 pins (40 total). Sometimes one or more of the pins is blocked off.
A floppy cable looks very similar to an IDE cable, but measures 1 3/4" wide. This cable has 2 rows of 17 pins (34 total). Sometimes one or more of the pins is blocked off.
A serial ATA cable is maybe as wide as your little finger (about 1cm wide).
The color of the cables is unimportant, but generally IDE and floppy cables are grey-white, occasionally black, and SATA cables are generally red, but blue or black is common too.
Most Dells's bought in the last..year maybe? no longer have floppy drives internally. Does yours? I ask because it sounds like you have a floppy drive cable, in which case you don't need to disable your onboard floppy drive controller, but rather set it to the correct drive. (3.5" Floppy, 1.44MB). Check that the floppy cable is plugged into the drive (hopefully the right orientation), and that the drive also has power going to it (separate cable, these are 4-wire cable, red black black yellow and you will have wires like this running all over inside your computer).
It also sounds like you have at least two IDE devices in your computer. These can be hard drives and optical drives. Most computers usually only ever have one hard drive, and one optical drive, but 2 optical drives is somewhat common as well.. generally the two optical drives are plugged into the same cable, one in the middle, one on the end. (FYI - by optical drive I mean CD-ROMs, DVD-ROMs, etc. including burners). Since you brought up RAID, your computer can have more than one hard drive (generally two in this case).
If you can let us know what drives you have and how many of each...(isn't this fun??
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