Sapphire ATI Radeon X1950 Pro Graphics Card. AGP 1.5V (AGP 2.0/3.0 standard) signaling is used by 4x/8x graphics cards and is incompatible with older 3.3V (1x/2x) slots. These cards have a single, rear-positioned key (slot divider) and operate at speeds of 1x, 2x, and 4x (for 1.5V) or 4x/8x.
eBay