This little machine came with Win Vista, which I upgraded to Win7 at some stage. At same stage, the box was flagged for a free Win10 upgrade, which never came.
So, I decided to plug in a Win10 install thumb drive and guess what, Win10 upgraded.
However, and here is probably why the upgrade never came via the internet: the Nvidia ION graphics chips was not natively supported by Win10.
No big deal, I though, lets go to Nvidia and download the drivers. Well, no such luck. The Win10 driver package did not install.
What now? Well, there still is this slim chance that Acer provides some drivers. In the respective driver download area, no luck for Win10. However, they still offer the Win7 64bit driver which is called "Chipset Driver For MCP7A-ION". And this package installs on Win10 just fine. After a reboot, all GPU function were available.
So, running Acer REVO R3600 under Win10 is not problem at the end.