I too have the PITA intermittent blank right hand side of the screen on my HLR5688W. It has now gotten to the point where it can happen every few minutes if I'm watching HD source content, especially commercials for some reason.
A service tech I trust has given me the DMD board replacement option "if I can find the parts." Apparently, from other postings here and my own experience Samsung is not very helpful. I was also warned not to give a deposit to the parts department at "The Geek Squad" because they simply hold your money and never deliver the part because they, like everyone else, seems to be having problems finding it.
My set is probably an "early" rather than a "late" version with a manufacturing date in 2005. Is there any known source for a "good" part for this set? Frankly, like another poster, this experience has soured me on Samsung although it seems clear that the blame may lie in part with the folks at Texas Instruments.
Why aren't there any laws about manufacturer supplied replacement parts any more? A "lemon law" like the one passed to deal with poorly designed high failure rate cars may be needed. Back in the day, import motorcycles had a requirement place on them that the manufacturer would supply spare parts and/or the importer provide for repair services for ten years from the date of purchase. My experinces with Butler and Smith over crankshaft repairs to a 1954 Victoria Bergmeister 350cc road bike in 1962-3 educated me on the problem with a law that has no enforcement agency actively supporting folks who had been treated badly. They were required to possess the "jig" needed to split the crank shaft and reallign things after the bearings were replaced. I was willing to send in my crankshaft to have the work done but they refused to use the jig and instead offered me the only "NOS" complete crankshaft in stock in North America for twice what I had paid for the motorcycle. Needless to say, that gem of a road bike ended up as something else when I sold it as junk to a guy who lengthened the frame four inches and dropped in a VW motor to make a drag bike.
It appears that this HLR 5688W owner will be forced to generate a lot of e-waste and will become committed to seeking legislative remedies needed if a sustainable economy is to ever be achieved. Making things designed in a way which causes rapid deterioration and failure in support of market volume and "planned obsolescence" must be a thing of the past for the next generation if global catastrophe is to be prevented.
Anyone... a source for the DMD board for this set?