I have an Imac G5, 2,1 GHz, 1,5 GB DDR2, which I bought in nov. 2004. I had no troubles in using it until two or three weeks ago. I ussualy work in FCP 5.0, DVDSP 4.0, but my wife use Safari, Skype, Tommato torrent, Yahoo Mess. I also use Vidi to watch TV. I also used to play Luxor. The Computer did his work very well, with all this apps open.
But, in a day, when I played Luxor, the computer enter in Standby mode, turned off the screen and the fans make an higher noise than ussualy. This happens several times. Now only with Safari and Tommato when I open a site with kids game, it enters in standby mode and did that noise on fans. Do you have any ideea what's happend? It's the CPU, the memory. The iStat looks prety normal: free memory about 1 GB, CPU idle 50%. Many thank in advance!