If it's a SATA hard drive, they may, or may not be necessary.. In addition, although everything you've listed looks like a good starting point, I have noticed that Intel has a newer IDE/Chipset driver.. After installing the one you've listed, you might visit the Intel site and use the newest one.. I found the new one corrected a few blue screen issues on the HP downgrades I've performed..
Of course, since you didn't list the model number for your Gateway, it's a little tough to make any further guesses.
Hope this helps.
Grif
Alright, I'm going to try downgrading my crappy Gateway tower to XP in a little bit, just seeing about my drivers here. I know my video driver (just gotta go to nvidea's site). My IDE, LAN, and Sound drivers are all listed here: http://www.ecs.com.tw/ECSWebSite/Downloads/ProductsDetail_Download.aspx?detailid=727&DetailName=Driver&DetailDesc=&CategoryID=1&MenuID=6&LanID=0 (note: I'm not 100% sure this driver is correct, CPU-Z lists my Mobo as ECS 945GCT-NM 1.0, but that site doesn't have the "-NM" suffix selectable at all. I figure that's about all I'll be needing. Confirm/deny?

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