I was told to have a look at the power board - Televison & Video

Where did you get your used boards from Jerrard?

Iv the voltages are low, pull the power line from each of the other boards to see which one is dragging the voltages down. If none ovf the voltages return to the correct value, then the power supply board is gone. You can get all the repair parts you need from here:
http://www.shopjimmy.com/

Check for power to module board to verify , if no power board might be good !

It's somewhat skilled work to replace the Power Supply board. Contact any service technician.
http://electronicshelponline.blogspot.com/

Samsung told me this was a common problem and I would have to have it serviced by an authorized repair facility.
My problem ended up being the internal power supply, but they also told me the main boards burn up.

There are two boards in your TV - power board and main board.

if it's not one it's the other.

Whoever told you that it was the power board has simply made a brave guess at your expense.

This is why it is not always better to listen to free advices.

You need to find out mare as to what else that the repair shop left out, all the coonectors need to be checked to see if they are in correct place, beside missing the SPEAKER board, no other boards are missing? I would go back and have them put all the old boards back inplace, he may have takebn out the inverter board and others to use for other repair jobs.
You may need the service manual to figure out.
If you are going to DIY and have proper tools, electronics knowledge, and know safety precaution then please read on:

Basic LCD monitor and TV troubleshooting guide:
http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide
http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting
http://www.fixya.com/support/r7406380-tv_training_manuals
Failed TV and Monitors: http://s807.photobucket.com/albums/yy352/budm
Learn about bad caps: http://en.wikipedia.org/wiki/Capacitor_plague
Parts: www.shopjimmy.com
Capacitors kit: http://lcdalternatives.auctivacommerce.com/Default.aspx he can make you a set of caps.
Or www.digikey.com, just make sure to use caps with low ESR, 105c, high ripple current and long life rating such as PANASONIC FM or FC series.
Please post back what you find.
Please leave rating if it helps.

Tv having a power supply board problems,not giving the tv the right voltages anymore.That the board,where the power a/c cord plug into it.Try website like Ebay.com to buy a refurbish power supply board for the replacement.

If you are handy with a soldering iron you can do the repair yourself. 90% of power problems stem from cracked solder joints on power board & convergence board. All you need to do is heat up the existing solder and add a little fresh solder to the joint. I had a power problem on my Toshiba 50". Service guy told me a new board would be $165 + $150 for labor. I wasn't paying that so before trashing it I grabbed my soldering iron and resoldered every joint on the power board and convergence board. Bingo! No more power problem and it only cost me $25 in supplies.

HI BENJIMAN, I HAD THE SAME PROBLEM AND COULD NOT FIND NOTHING WRONG THEN I SEEN THAT THE POWER CORD WAS MOVING WAY TO MUCH, BUT EVERTHING LOOKED OK ON BOTH SIDE OF THE BOARD, WHEN I UN SOLDERED THE TWO LEADS IT WAS BURNED UNDER. I RAN JUMPERS AND BINGO I HAD PICTURE AND SOUND. THAT WAS MY PROBLEM GOOD LUCK.

CHIEFMIGGYMAN