G5 won't boot need help

Ok so a friend of mine got a G5 tower from a co worker and they said they didn't know much about it etc. So we got it home and hooked it up when i press the power button the light comes on but then goes off and i hear a "click" sound . i don't even hear the fans start up just a click sound. i pulled the battery out for 1 hour and put it back in i also pressed the PMU button and same thing so i am asking for help. From what i can see it has 1 gig of ram ( 2x512 ) and its a 2 ghz DP/PCI-X is this thing dead ? thank you viewing!!!

 

Ty for the replies I guess I'll hunt ebay for a Power Supply and see if i can score a used one cheap and see what happens.

 

ok so here's an update..I removed both processor's and tried to start up with just one... on the first try i removed just the bottom one first and tried to start up and nothing so then i removed the top one and placed the one that was in the bottom into the top spot and when i pressed start i can hear the fans come on and i had a red light !!! ( had see thru door off ) did not get a boot chime but at least now the fans spool up ... is it possible to run this mac with just one or do i need both processors ??( will order one either way) thx

 

so after toying with this today i got it to boot up and chime after i installed just one of the processor's i found out that the Lithium battery was also dead lucky for me i had a spare so i installed the battery pressed the pmu reset on the board and its booting up !!! yay so now since i know for sure that one processor is no good i went on ebay and found a matching set for a good price so once they get here will install them and all should be good