For the 2014 version, the requirements were significantly lower than modern versions, making it popular for "portable" use on older hardware: Minimum Requirement Intel Pentium 4 or AMD Athlon 64 (2 GHz+) Operating System Windows 7 SP1, Windows 8, or Windows 8.1 RAM 2 GB (8 GB recommended) Display 1024 x 768 (1280 x 800 recommended) About "Portable" Versions
Adobe now offers an official, browser-based version of Photoshop for Creative Cloud subscribers. This provides true portability, allowing users to edit files on any computer via a web browser without installing the desktop client. Adobe Photoshop CC 2014 V15.2.1.257 -Nov 2014- Portable