Ideally, it'd probably be a good idea to replace ALL the caps, including C1, while you're at it, but I'd concentrate first on the flyback, Q3, and maybe CR1 first. Get if functional again and go from there.

Not sure if it's good to post here, but here's a link to a PDF version of Larry Pina's Mac Repair and Upgrade Secrets. This book will tell you everything you need to know.

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