Wow, some amazing first PC's in this thread!!!!!!!!
First thing I used was an original Atari and I think it just had Pong on it?
First official "PC" was an 8088........Can't even remember the MHz or memory. I had to load the operating system from a floppy disk. Then I upgraded it and installed some huuuuuuuuge hard drive. I think it was a 4 megabyte drive. LOL
I then wrote a hard drive parking program to keep from damaging the hard drive when I would have to transport the system.
Of course the monitor was monochrome.