<!-- from fixya rte -->Picture freezes intermittantly - Samsung HLP4663W 46" Rear Projection HDTV

Fault at its main digital board. Short circuited component/s at it. Contact any service technician; or the authorized service center. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts.
http://electro-medical.blogspot.com/

In most cases, the main board might have to be replaced. If so, a software [firmware] update too might be necessary.

There is an fault for sure. When you are not a tech, you don't have to know what is wrong. So when the solution from The Knight does not help, contact a tech or visit a repair shop. Ask what they will charge in advance to see if it is worth repairing the TV.

Sorry can't help on this. Presumably you've switched off/on at mains and checked all connections secure. Would a factory reset help, see tips how to do on fixya, although not sure if you would lose library data.

If it lock intermittantly, then check the signal from your aerial.

Hi.. Sorry to hear that the Picture is freezing.. Here are some of the steps that you can try:
*Try to connect a different video source with the TV like DVD Player, Blu-ray player and check.
*If the issue persists, disconnect the power cord and reconnect to a different wall outlet without the Power surge protector.
* If the issue persists, you need to contact the nearest service center to fix this.
Yes, you were correct many LCD TVs have problems compared to this TV.

replaced main board

Sounds like a network problem. Is your internet connection intermittent? Or maybe a bandwidth problem.
Try using a cabled connection in case you are using wireless.
Close all other applications that are using the internet connection.

When ever the picture freezes intermittendly the problem is usually poor connection on the signal line (antenna or connection on tv) or poor reception. Could be the tuner if the tv has one.To eliminate the tuner possibility try anther tv set if possible.
If you still cannot figure out the problem,let me know what kind of set up you have connected to your tv set.
Do you have a satellite or cable box and if you have splitters.

freeze like the picture is in pause?

picture freezing is desired function on the remote and handled mainly by the "picture and picture" circuits. but the video that is involved and processed there is handled by many circuits and microprocessors.
what you describe is an intermittent heat related problem if you almost can set a watch to the the shut-off time. you can feel, if your a tech, what part is running hot with a finger or start freezing a suspect part with freeze spray and see if stays on long past overdue. make sure your vent holes in the back are not covered and keep the back at least 1/2 foot from the wall.

Punch yourself in the face REALLY hard and then throw the TV out the window and buy a 60" Plasma or a 52" LCD