For me, one of the differences has to do with expectancy. 'going to be providing' has a greater degree of expectancy, greater certainty. But it is nebulous. Foggy.
"The server is going to provide something - Just for this time" This one is kind of indefinite, but does have a one time sense, could be used for a question about what is going to happen in a particular case, ie server has been prompted, now waiting for response.
"The server is going to be providing something." This one could be used when is a case of how server has previously functioned, so we have seen it already working in a particular situation. And now we have that situation again, and so we have expectation that 'it will be providing something'.
The idea about the imperfective/perfective is reasonable, but in English it isn't such a clear difference as in Russian.