Samsung on Tuesday released its 31-series LED-backlit monitors. The budget-priced lineup is made up of the 20-inch BX2031, 21.5-inch BX2231, 23-inch BX2331 and 24-inch BX2431. Each is meant for students and small or home office users, and uses as much as 40 percent less energy that comparatively sized CCFL (cold-cathode fluorescent) monitors.