yes +1 on that
2007 means logicboard or PSU or both , quiet common after that time... sorry but logicboard is beyond a economical repair , unless you get a really good price made for the replacement logicboard which i doubt as they start somewhere in the region of $600 -$900 , the costs will hover usually above a new mini and just below a new iMac 21.5

if its only the PSU then its cheaper , but as the iMac is already 3 years old i guess more parts will follow soon , so you should think about if its not more economical to look for a refurbished iMac 21.5 base model