Version 0.8.7 was built before the shift to a heavy client-server architecture. It runs efficiently on older laptops and PCs with limited RAM.
For students studying for the older CCNA/CCNP curriculum, 0.8.7 provides a straightforward "drag-and-drop" experience for IOS images without the complexity of configuring GNS3 VMs. gns3 0.8.7 download
The most reliable source is the GNS3 GitHub repository . While you may have to scroll back through the years, the official project maintains an archive of older releases. Version 0