What's the model #s of the DRAM - will guess the 'newer' DRAM is actually a newer line of DDR3 made with High density memory ICs (chips) and not compatible with your H55 mobo chipset
my old ram= transcend 4gb ddr 3 1333mhz
new ram= corsair 4 gb ddr 3 1333 mhz
old ram =pc works fine
new ram =pc keeps restarting at boot screen
when both rams inserted =pc keeps restarting
i have tried to clear bios also