Having seen the original query and one request for further information but no resolution: my experience/query is similar.
DPF-D80 is always on and appears to have functioned as expected for at least the last 18 months.
40 images are held in internal memory. Images are not read from any plug-in card media but downloaded by wire from home computer. No new image has been added to frame memory for a couple of months.
Yesterday the screen was found to be blank and with the green power light on.
Tried rebooting by putting on standby, switching off mains power at the transformer plug and then repowering; the picture frame worked briefly then screen again went blank.
Tried re-booting again and established that the file of images was intact before screen again went blank.
Powered down as before and left overnight.
This morning, switched on and found the screen display worked and images changed as expected for about an hour before screen blanked and as before the green power light remained on.
This afternoon, conected to via USB device cable to home computer and all 40 images stored within the picture frame were visible on computer screen when viewed via USB link.
Subsequently, in stand alone mode, I was able so use the scroll buttons on the frame to view each of the 40 images on the picture frame.
I then left the picture frame powered up: after a few minutes the screen blanked but the green power light remained on.
Pressed power button to standby and back to on - screen display for a few minutes only.
Repeated warm start as above, changed 'order' from 'random' to 'shoot date' and 'interval' from '5 minutes' to '10 seconds'. This time the screen displayed for over 30 minutes before blanking. When blank the screen did not instantly respond when I pressed any of the buttons, either on the frame or on the remote.
I hope there is enough here to enable someone to suggest a fix.
