I bought a new computer no more than 5 months ago, and the whole time I kept getting repeated blue screens. I ran Memtest in each slot with my single stick of RAM and three of them reported errors, while one just crashed the PC completely. How can I be sure it's my RAM and not my Motherboard? I only have one stick of RAM. Should I send the RAM back and get new stuff and see if that works? I need to be sure it's not my Motherboard.