The BIOS reads each stick as 2 GB instead of 4GB. The stick are DDR3 1600.
The supported memory clock speed for the processor is 1066 MHz but besides that I would ask Crucial* regarding the memory density as it may not be compatible (as you may need to use 2 Gb memory technology).
“DDR3 1600 or higher memory support on this motherboard requires compatible XMP enabled memory or advanced knowledge of BIOS and manual memory tuning. Individual results can vary.”