 This phase 1 trial studies the side effects and best dose of dimethyl fumarate when given together with temozolomide and radiation therapyRT in treating patients with newly diagnosed glioblastoma multiforme GBM. Dimethyl fumarate may help radiation therapy work better by making tumor cells more sensitive to the radiation therapy. Drugs used in chemotherapy, such as temozolomide, work in different ways to stop the growth of tumor cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Radiation therapy uses high energy x-rays to kill tumor cells and shrink tumors. Giving dimethyl fumarate with temozolomide and radiation therapy may work better in treating glioblastoma multiforme. 