2 x 240-pin DDR3 DIMM slots. While the chipset can technically support up to 8GB, many OEM versions of this board are capped at 4GB maximum (2GB per slot).
The board supports a wide range of Intel processors with Front Side Bus (FSB) speeds of 800, 1066, or 1333 MHz: Core 2 Quad, Core 2 Duo, Core 2 Extreme. g41t-ad v1.0 motherboard manual