There are three main courses in computer architecture, one in VLSI design, and one in current topics in computer architecture. Most are cross-listed as Electrical and Computer Engineering courses with the same number. CS 552 is the basic course. CS 752 and 757cover advanced topics in computer architecture, CS 755 covers advance topics in VLSI design, and CS 758 covers current topics in designing and programming microprocessors. CS 752 is offered every semester either by the Computer Sciences Department or the ECE Department. CS 757 is usually offered in the Spring either by the Computer Sciences Department or ECE Department. CS 755 is usually offered in the fall under the auspices of the ECE Department. The content offered in CS 758 may vary significantly based on the instructor. The Ph.D. qualifying exam requires knowledge of material covered in CS 552, 752, and 757 and some extra readings.
Past exams
http://pages.cs.wisc.edu/~karu/qualwiki/