Sorry to post in an old thread, but I want to share my experience with repair of this power supply.
Unless they were shorted, you did not need to replace the mosfets in the secondary...
Since you have already replaced the bad capacitors in the 12V and 24V secondary, check if you have 5V standby voltage.
If you have 5V standby, please try replacing capacitor EC4 (near the lower transformer in the middle of the board). It should be a 33uF/50V capacitor, but mine tested out-of-spec at only 15uF. Replacing with a new 33uF/50V should restore functionality to this power supply and allow you to turn on the TV.