Let's hope our resident guru pitches in but do try the usual canned air cleaning and given the age it may be time to strip it down to replace old heatsink compound. This is not a trivial task.
Bob
Model Name: PowerBook G4 15"
Model Identifier: PowerBook5,2
Processor Name: PowerPC G4 (1.1)
Processor Speed: 1.25 GHz
Number Of CPUs: 1
L2 Cache (per CPU): 512 KB
Memory: 2 GB
Bus Speed: 167 MHz
Boot ROM Version: 4.7.1f1
My screen flickers, and gets real blurry when cpu in understress.. It recently happened, I can play any games, but can still watch movies and surf the net.. My fans are working, but everytime I try to play a game "WOW" lines start showing on screen and gets blurry, until I exit out of game.. I changed my setting in reduced in system pref.. I was wondering if anyone know if the Graphic chip is bad, or the inverter??
Ty

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