An Artifical intelligence lives in a coffin-sized robot-space-ship, placed in planetary orbit. It has solar power collectors, ion engines, and the capability to mine asteroids for materials, which it can then use to produce stuff. It was built with the ability to produce engines, power sources, electronic chips, and structural parts of various materials and shapes.
-It does NOT have any kind of warp drive available, nor does it have nuclear technology available, like fission or fusion. While it does have electronics, it does not have a functional framework to explain quantum physics.
-It DOES have electromagnetic communication technology, lasers, and ion drive tech, as well as some other technology like Peltier junctions, batteries, and chemical fuels.
-Its computer hardware and (especially) software, and the tiny asteroid mining/factory component, are the only technologies it has that is more advanced than ours.
Its creators went extinct shortly after putting the AI into orbit, leaving its original purpose of creating habitats, observation labs, and factories in space, half pointless.
It took years before the intelligence finally accepted it was now alone, and years more before it chose to adjust it's primary mission to the computation of some mathematical solution. It knew it was going to need far more processing power than it had now, alas, it did NOT realize the mathematical problem would never actually be solved by simply using more processing power. Continuing to build factories, but not habitats, it began to expand its processing capabilities.
While the AI has swift processing powers and can perform logical deductions, it is quite unimaginative and is incapable of coming up with any new inventions. At best it can incrementally improve/evolve existing designs.
When our brave explorers finally encounter the AI, it is one million years old.
What kind of capabilities (mental and physical) could such a machine have, and how vast would it be, after 1 million years of, technologically stagnant, self-improvement? Keep in mind the AI has no need to worry about standard life support; it just needs a source of power, and a way to dump excess heat. While not exactly traditional life support, it DOES still need to collect materials in order repair itself and build more capabilities.
Let's assume the star system the AI was originally created in was very similar to ours, and that our "brave adventurers" are the first intelligence the AI has met since its creators died off.
The intention of this question/adventure/story is to explore what very limited technology is capable of, over a vast period of time.