Desktops :: G5 Freezes While Startup In Winter

system info:
Dual 1.8GHz PowerPC G5
2 GB SDRAM
OS 10.5.6

My computer is 4.5 years old. And every winter for the past 3 years it's had troubles starting up in the cold mornings. Gradually getting worse each winter.

Today wasn't too bad.. it started up on the 2nd try. But on a particularly frosty day it might take 3 goes.

It freezes anywhere between the grey screen to the loading wheel to the desktops appearance.

Sometimes it freezes and gives the message to switch it off by the power button.

On occasion it freezes and shows me this: [URL]