Official versions of Boot Camp 3.0 (64-bit) are not available as a direct download from Apple's website, as this software was originally distributed exclusively on the Mac OS X 10.6 Snow Leopard
If Boot Camp Assistant fails to download drivers: Bootcamp 3.0 64-bit.exe Download
If you need drivers for an older Mac (e.g., 2009–2011) and don’t have access to macOS: Official versions of Boot Camp 3
: For those without the original disc, some users turn to the Apple Bootcamp Support Drivers Version 3 on Internet Archive , though these are third-party uploads and should be used with caution. How to Install BootCamp64.exe Scan the file with up‑to‑date AV and, if
: This site hosts Apple Boot Camp Version 3.1.1, which includes both 32-bit and 64-bit versions extracted from the Snow Leopard DVD. 3. Apple's Official Support Page (Later Versions)