Hi Ziesta,
Without any more information it is hard to give any clear help? You say it wont boot up. Is there any messages being presented on the monitor or won't the computer turn on at all?
If you don't have surge protection, power surges can cause havoc with computer components. One of the first components to be fried apart from the psu would be the RAM sticks. Though it could be the Mother Board or cpu as well. (you could ask to borrow a RAM stick and replace the ones you have and see if it's that.
If your project is really important, I would firstly give more information here. Copy down what the messages on the monitor say. There should be some sort of error message; or alternatively, where does the boot up sequence end?
If the computer looks like it's been fried, the next best thing would be to transfer your hard drive to another computer so that you can then retreive the files you need.
With todays plug and play hardware, it's easy enought to plug your HDD into another computer.
Sorry I couldn't be of more help.
Regards
Stephen