Using Onyx to repair permissions under admin user and then changing display resolution (with blue screen and forced restart via power button) has given me 1280x1024x32 with QE/CI on the system without changing anything else.

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MacBook Alu 2,4 GHz, 4GB, Seagate 7200.4 500GB, iPhone 3G 3.0
Shuttle SG33G5, Intel C2Q Q6600 2,4 GHz, 4 GB, Samsung HE753Li (retail Leo 10.5.6), Seagate Sata for Vista, PX-810SA, Nvidia 9600 GT 512MB

SG33G5 runs Retail Leopard 10.5.6 (vanilla) thanks to boot123!