Most of the time I don't pay attention to dpi. Probably should.
I mostly pay attention to the pixels by pixels size of the map. Some maps I have created are 8000 pixels by 4000 pixels for global maps. I think the largest I made was 50,000 pixels by 25,000 pixels. But that was on my Linux workhorse with dual Quad-Core AMD processors and 32GB RAM. However, I keep updating that machine and the next update will include two more Quad-Core processors. Afterwards, I plan to update the amount of RAM. Then again, the machine is a SGI Workstation based machine...
For Windows, about the largest I will go is about 10,000 by 5000 pixels. Windows does not seem capable of handling more. Gads, I hate Windows...
rmfr