Issue: This article provides the system requirements for AutoCAD 2005. Solution: Intel Pentium III or later with 800Mhz Processor.
If you want, I can:
Instead of searching for outdated, risky portable versions, consider these official options: AutoCAD Web autocad 2005 portable
It can run on systems with minimal RAM and older operating systems. How to Use AutoCAD 2005 Portable on Modern Systems Issue: This article provides the system requirements for