I AM USING DH55PJ INTEL MOTHER BOARD AND INTE CORE i7 CPU @2.93 GHS PROCESSOR.NOW I AM PLANNING TO UPGRADE RAM TO 8GB . WHICH ONE TO CHOOSE 1x8GB OR 2x4GB I HAVE ONLY 2 SLOTS FOR RAM I HAVE MY OLD (2YEARS) RAM WITH ME 2GB SO IF I CHOOSE 1X8GB SO TOTAL MEMORY WILL BE 10 GB .