First of all, RAM isn't a drive, it's a chip.
Second, looking at the motherboard won't tell you how much RAM you've got.
Third, if you've purchased a legal version of FS, the dealer can be as dodgy as he/she would like. A legitmate version is a legitimate version.
Fourth, when FS itself needs 64mb of RAM, and you've only got 56mb of RAM, and you wonder why a program won't work, compare the two numbers. If the number you have is less than the number it needs, that's more than likely the problem. Yes, there could be other issues, but that's the most logical to begin with, because even if you correct the other issues, by failing to meet the minimum requirements, the program isn't going to work.