Do use Cubase 6.5 if:
: Cubase 6.5 was originally designed for Windows 7 and Mac OS X 10.6/10.7 . While it may function on newer systems like Windows 10 or 11, it is not officially supported and may experience stability issues. cubase 6.5 download
Are you looking to on an older machine, or are you trying to get Cubase 6.5 running on a modern OS ? Shifting Cubase 6.5 to Windows 11? - Steinberg Forums Do use Cubase 6
Note that Cubase 6.5 was designed for older operating systems. Running it on modern versions like Windows 11 or macOS Sonoma may cause instability or require "compatibility mode". Steinberg Forums Minimum Specification (Legacy) Operating System Windows 7 / 8 or Mac OS X 10.6 / 10.7 Intel or AMD Dual Core CPU 2 GB minimum Disk Space 8 GB of free hard drive space USB-eLicenser (Dongle) is mandatory for license management 3. Activation Guide Shifting Cubase 6