HELP !! HP w1907 monitor comes on till it warms up I guess and then goes black, but pwr button light stays on. Shut it off and then back on again, comes back on for a while then black again. Been told to replace all cap's on main board, would like to get a little more specific than that. New twist, after it going black, pwring down and then back on, it seems to be staying on....this is driving me nuts, it would be fine for me, but its a customers, so gotta fix, please help if you can....thx