Complex sentence: Machines supporting the Architecture habe been sold under the Brand System/390 or S/390 for short and underwent 6 Generations from the beginning to the end of the 1990es and it was the only mainframe architecture implemented first with bipolar then later with CMOS CPU electronics.
Split into simpler sentences: Machines supporting the architecture habe been sold under the brand System/390 or S/390 for short, and underwent 6 generations from the beginning to the end of the 1990's. It was the only mainframe architecture implemented first with bipolar then later with CMOS CPU electronics.