This pilot phase II trial studies how well giving high dose busulfan together with bortezomib works in treating patients with high risk multiple myeloma undergoing stem cell transplant. Drugs used in chemotherapy, such as busulfan, work in different ways to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. Bortezomib may stop the growth of cancer cells by blocking some of the enzymes needed for cells growth. Giving busulfan together with bortezomib before a stem cell transplant may kill more cancer cells