Ok, download a copy of MemTest86+
, put it on a usb flash drive (any will do, the program is quite small) and test your ram for a few hours.
If MemTest reveals no issues, then I would contact Acer for warranty service. If the ram isn't the culprit, you could be looking at a faulty hard drive or motherboard, both of which Acer should be able to replace under the warranty. If the ram is the issue, Acer should also be able to replace that under the warranty.