It should work just fine. Notice that although the computer came with an EIDE 66 hard drive, the motherboard actually only supports EIDE 33.
Beware of the possible BIOS problem with that motherboard:
ISSUE: When viewing the hard disk drive in the BIOS Setup Utility, the size of the hard disk drive does not display 75 gigabytes (GB). It displays 65535 megabytes (MB), 65 GB, or another size smaller than what is installed. This only happens when the hard disk drive is connected to the motherboard controller. This can also be seen if, during the start up process, the TAB key is pressed when the Gateway logo is displayed.
RESOLUTION: This BIOS Setup Utility setting is only cosmetic and in no way hampers the performance of the hard disk drive. The hard disk drive formats to the full capacity, and Windows identifies it correctly.