jim1954 Loc: Minnesota

I purchased a picture frame, which has a display area of 12" by 9". Per the documentation it displays 1024 pixels x 768 pixels. Math logic suggests to me that the frame displays 85.333 dpi.
Based on that, I'm thinking it would be best to resize or crop my photos to 1024 x 768 pixels (or 12" by 9") with a resolution of 85.333 dpi to fill up the frame, get the sharpest display output, and most effectively utilize the space on the thumb drive.
Is my thinking on this correct, or would there be any advantage to loading denser (say 200 or 300 dpi) or larger jpegs?

CHG_CANON Loc: the Windy City

DPI / PPI has nothing to do with the digital display of your image. The only issue is the length & width dimension as expressed in pixels. If the frame is 1024-wide, sending an image file that contains more pixels than 1024-pixels on the long side is a waste as the image will be sized to the dimensions of the frame, or possibly, cropped to the frame dimension, you'd have to test which occurs

This post, in section = What are DPI / PPI?, discusses this specific issue: https://www.uglyhedgehog.com/t-512745-1.html

To your question, yes, set your image dimensions to match the frame as measured by the length and width in pixels. I wouldn't go back and recrop older images. Rather, I'd set my LR export (or similar software) to 1024px on the long edge / side as well as using only landscape-oriented images.

Also if possible from your processing software, rename your files to an 8x3 format. If you spend some time reading complaints on various digital frames, you'll see the more knowledgeable authors can isolate the display issues to "large" file sizes and / or "long" file names. A batch process like a Lightroom export preset can control these issues such as renaming the resulting files using a counter from say "F0000001.jpg" upward. The files will typically display in date-order so the filename doesn't control anything.

I updated my SD card over the past weekend with recent edits, increasing the image count to 8843 images. Because I revisit older images without keeping track of which are updated, I re-export the contents and replace all files on the card. I let the export run overnight or while away from the computer for an hour or so for this long-running process to run to completion.

Longshadow Loc: Audubon, PA, United States

I didn't bother with all the thinking, I just put 50 large JPEGs on a card and stuck it in the frame.
I'll let the frame worry about how much of what it wants to worry about.
They look great.

jim1954 Loc: Minnesota

CHG_CANON - thanks for the reply and the link. Very helpful!