Thanks for the reply, bigbang. this is for an acer aspire m5640 system that is not working right now. Based on the many threads i've read here, the motherboard is also the culprit. I am not inclined to get exactly the same motherboard from acer. i thought i'd look for an alternative, an asus or gigabyte but i'm not sure which one (model) would be compatible with for acer's M5640. Currently, it has 4gb or RAM, an optical drive and hdd. That's it.