Hi Rikku. Whether any of the computer components are damaged will depend on the quality of the power supply. A well specified supply may have output protection whereby if a voltage exceeds a certain level the output is turned off. This is not always included in a design so there can be no certainty either way. A new power supply needn't be expensive. You can get a 400W supply from Ebuyer for only about £10 plus postage.click here. You can, of course spend a lot more, but the £10 job will tell you if your computer is working. I'm using one with my 1.6G Duron system, it's quiet and is working fine.