How to Test the DMD Board and/or Power Supply?

[oldtech]

My HL-R4677W has not responded to transplant/treatment [replaced lamp and ballast] from Samsung's authorized parts seller]. Set still cycles as before with no picture or sound and the fans and color wheel spin when set is powered up. Also, the whistling noise still cycles from the center of the set. I checked the two pin jack on the DMD board that supplys voltage to the
ballast through the brown and blue leads and it reads a nominal 315VDC. What should it be? Also swapped the original light engine for the new one to eliminate a defective "new" lamp. No help.

What other voltage readings are available for troubleshooting the DMD board and Power Supply? Thanks in advance.

[Eddie]

Where did you buy the parts? Samsung Authorized Reseller means nothing to this forum. We go with OEM parts from Authorized OEM providers.. a whistling noise might be a color wheel