What is the make/model of the PCI IDE adapter you are using? I assume you have something installed into your motherboard for the drive you are referring to.
If you are using the motherboard's built-in IDE port, make sure it is enabled in your BIOS. Also the drivers for your motherboard can be found here:http://www.gigabyte.com/products/product-page.aspx?pid=3443#dl
Windows 7 should load a generic IDE driver for the IDE port if it is enabled. Also, with IDE devices, you have to have the jumpers set properly for single drive or master or cable select. What are your jumpers set to on the HDD itself?