I started a backup on my PC then got a message that there was not sufficient room for the backup. I absent-mindedly turned it off before I went to the shop to purchase an external hard drive. Came back and when I press the on button, the light comes on yellow but noting appears on the screen (monitor says there is no signal) and the light never turns blue - normal running colour. I figure that it doesn't have enough memory to boot and am wondering if I purchased some RAM and installed it, would the machine automatically recognise the extra memory and start up or is there something else that would need to be done?