The Internet Archive hosts various "official" disc images uploaded by users. Look for "Retail" or "OEM" versions that haven't been modified.
Unlike the 32-bit version (limited to 4GB), the 64-bit version can utilize up to 192GB of RAM. Windows 7 Ultimate 64 Bit Iso
: Always verify the hash of any ISO you download from non-Microsoft sites to ensure it hasn't been tampered with or infected with trojans. Unique Community Fixes & Projects The Internet Archive hosts various "official" disc images
Always verify using tools like Get-FileHash (PowerShell) or certutil -hashfile . Windows 7 Ultimate 64 Bit Iso