No sound, no piciture, when i turn on the power.

If your QN75Q60TBFXZA screen keeps flicking and cycling, it could be caused by a few different issues, even if you already changed out the CPU board:

1. Check the power cable to ensure that it is securely plugged in and that the outlet is working properly.
2. Check the cable connections on the back of the TV to ensure that they are all securely plugged in.
3. Check the power supply to ensure that it is functioning properly. If the power supply is faulty, it can cause the screen to flicker and cycle.
4. Check the main board to ensure that it is functioning properly. If the main board is faulty, it can cause the screen to flicker and cycle.
5. Check the power supply cable connection to the main board. If the cable is loose, damaged or not properly connected, it could be causing the issue.
6. If the problem persists, consider contacting Samsung customer service or a technician for further assistance.

It's important to note that screen flickering and cycling can be caused by a malfunction or damage in the power supply, the main board or even the backlight. It's also important to check that all the connections are secure and that no damage has been made to the cable or the board during the repair process.

there should be an "auto power" feature that should turn the unit back on once a signal is detected.

You need to replace your convergence IC's. You also need to check the resisters in the convergence circuit to make sure they didn't go bad.

sounds like a mainboard problem

Since you have replaced the Color Wheel, it sounds like you have not adjusted the Index Delay in the service menu. First reset all of the picture settings you have adjusted back to original factory settings. Then on your Samsung TV Remote and with the TV OFF, Press Mute,Power,123. This will turn on the set and put you in the Service menu. Look for the top setting and select or scroll to the OPTION setting and select and look for INDEX DELAY and select that. Once you have the Index Delay selected use the right and left buttons on the remote to adjust for a picture the has no abnormal coloring and while looking at a program adjust for when the blacks look black with no abnormal coloring. Once that is done, turn off the set then turn the set back on. Now the picture should look normal.

This is a common problem. Your convergence has gone out.

Common symptoms are...

1) 3D Video
2) Warped Video
3) Convergence menu does not adjust the red or blue correctly.

Go here for a solution...

http://www.fixya.com/support/r2861627-updated_convergence_problems_amp

This sounds like your closed caption has been activated. There are several closed caption options that aren't used for anything, and if you select one by pressing the cc button on your remote by mistake, it will cause the problem you're having. To fix the issue, locate the cc, ccd, or closed caption button on your remote. Press it until you the option "off" appear on the screen. Once you see "off," simply stop pressing the button and the word "off" will disappear.

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Hi You have power supply problem.Please go to ebay and buy cheaper price: AKAI LCT3201TD POWER SUUPLY MLT169A REFURBISHED CHAINA Thanks

it sounds like the power transformer maybe out on the set.it supplies power to the whole set and it sounds like it only getting partial power.

Perhaps the back light tube has blown. Not a repair job if it has- replace the camera- check Canon website