One thing you might want to check is to physically examine the board for burst capacitors. I used to own the D865PERL. There were two capacitors located on opposite sides and between the memory sockets. These are the ones that burst. Bad electrolytics can cause all sorts of odd behavior and intel used a bad batch of them as did many companies back when the board was manufactured which I believe was 2004.
If the board looks ok replace the jumper on pics 1-2 and try entering the BIOS when you first turn on, you might have to reset everything to your particular hardware configuration.
If the board does have swollen on top caps replace the board, it just won't be stable and give you lots of problems.
Brad: Thank you for the reply. I'd like to use the board again, so that I can re-use the memory, HDD, etc.
Indeed, there is a fellow selling a board like this one, and he advertises his as having "good caps". So I guess it's not my processor.
I did try manually entering bios. Keyboard and mice are "ignored" by the board. The red light on my optical mouse doesn't even come on...