Want to use old hard drive, but it's IDE cable. Motherboard is sata

You could buy an IDE to PCIe adapter card such as this one to plug into your motherboard:

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

or something like this:

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

That's just one, google "sata to ide adapter" - there's stuff as low as $13. Just make sure you don't get the one to plug a new sata HD into an MB with IDE.

Also are you sure you don't have an IDE port on the MB?

Here's the type of thing you need at the egg (same as gtvr listed above); it plugs into the back of the IDE drive:

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

NOTE that this one is so you can use an IDE drive (jumpered to Master) on a SATA mobo port. There is a different model that adapts SATA drives to IDE ports.
sminlal suggested a PCI card to give you an IDE port. Third alternative: you could consider buying an external enclosure that accepts an IDE drive and turn your old drive into an external drive.