At four months old, I think that after five minutes of faffing, a call to customer services would be in order. Although 512 isn't a lot of RAM, it is quite adequate and should give no problems in day to day operation.
Conan
PS Talk to Acer Direct. They will want the serial number, but you can bypass the shop and get better service. If you wish, PM me and I will find the appropriate details for you.