Samsung PS50Q7HDDX I am looking to buy a mains board for the above tv. the part number is as follow: BN94-01045B I would like to order one asap. any suggestion is welcome.

LN52A550P3FXZA TV. The T-con board is responsible for the image processing and video output, and a malfunctioning T-con board can cause a loud noise and a scrambled screen.
Other possible causes could be a faulty mainboard or power supply, damaged or loose cable connections, or a malfunctioning panel.
I recommend attempting the following steps before seeking professional help:

1. Check all cable connections to make sure they are securely plugged in and not damaged.
2. Unplug the TV for at least 30 seconds and then plug it back in.
3. Try a different input source to see if the problem is with the source or the TV.
4. Perform a factory reset on the TV by going to the menu and selecting Support > Self Diagnosis > Reset.
5. If none of the above steps work, it may be necessary to contact a professional repair service or Samsung customer service for further assistance.

If your trying to fix a TV watching youtube vids a lot of times that doesn't work so good as lot of people that post on there really don't know much about how a TV works. First thing to do is test the PS_ON pin on the power supply connector going to the main board for proper voltage, you should see about 3.3 VDC there when you turn the set on, what were looking for is does that voltage stay or drop to around 0 when the set powers back off, if it does you have a bad main, I know you said you replaced it but did you get a good used board, this model TV has a history of a bad EEPROM on the main, best place to order boards is shopjimmy.com do NOT order from ebay. If the PS_ON voltage stays ok replace the power board. Hope this helps

2017 LED TV M5300 M530D Series Owner Information Support Samsung US


Online chat available as well as telephone numbers to contact at above Samsung site.

Step by step online troubleshooting available.

Don't know much about TV,s but I would look for a reset. Either electronic option in the settings or perhaps a manual one on the TV to return the TV to its original factory software.

http://www.lcd-plasma-parts.co.uk/bn41-01180a-bn94-02845a-samsung-ps50b450b1wxxu-main-board
read the page above to get pointed in the right direction as it helps to explain what is required to order the correct board

Ebay....Get model number off of tv and number off of board itself...Find a powerseller w/good feedback...cheers!!!

you should try to replace the Timing control board (T-Con), it is showing signs of DC-DC converter about to fail for good. Good Luck!

TV Parts Universal TV Stands DLP Chips ShopJimmy Order the main board from here. On the back of the TV all the screws with arrows pointing to them have to come out. The back will come off then. get the number off the main board, then go online to order the part. It's easier than replacing a motherboard in a PC.

Hi
This is down to your Y Buffer upper board, Take the back off you tv and look to your left, you will see a main Y sustain board and then to the left of that 2 x thin long rectangular boards connected to your main Y baord and screen
These thin boards controll the picture top and bottom, get the number of the top thin board and replace it, of the top of my head it is .... LJ41-02760A look on Google or Ebay, these can be replaced cheaply at around £20-£25
I would stress to do this ASAP as it might take your main Y Sustain board out and these are expensive to replace!!.
This should 98% of the time cure your problem.
Hope this helps