Yeah, should have known better, will know better.
Anyways, moving on ...
I am not at the board at the moment, but I do remember it has some exposed copper pads that I assume are test points. Any of those for the 3.3V ?
What would be the easiest way to test for a blown 3.3V regulator ?

I received the new PanelDue I ordered today, came up as it should have.
At least I can be certain that the Wifi board itself does not have anything going on with it that would prevent the PanelDue from doing its job.

The nice thing is that i have another board. Was going to down the line get a duet 5 for it since its a small printer, but it will be a small printer with a big display.

An update. As I was preparing for brain surgery on this thing it has been sitting in its Anti Static bag for the last at least 48 hours.
Decided to plug it into the computer (same cable, was still plugged into the computer) and that is when i heard that lovely ba-da-bing sound. The computer recognized it and it showed up as a a Bossa port. I was able to flash it.
Currently the printer is mid print, so I cannot install it to verify that it works fully.
Either way, for anyone with a possibly similar situation, letting it sit for a while, and possibly in the anti static bag may be helpful.

I received the new PanelDue I ordered today, came up as it should have.
At least I can be certain that the Wifi board itself does not have anything going on with it that would prevent the PanelDue from doing its job.

Thank you, great ideas.
Definitely can scrounge up some old electronics around to practice on.

Ordered, will see how it goes.

Any recommendations how to go about replacing it ?
I welcome any suggestions.
I will watch some videos etc to better prepare in the meanwhile.

Removal:
I would assume I want to take the PanelDue as far apart as I can, remove the screen etc.
I do have a reflow gun, after taking apart my plan is to try to heat the chip enough to remove by pushing it off to the side? I could see doing this would possibly bridge some gaps.
Or perhaps before heating try to glue something to the top to use as a lifting device ?
I do also have a "solder sucker" and a Hakko FX-888D soldering iron with many small tips.
Should I try individually going around the legs and removing as much solder as possible ?
Also have copper desoldering braid, perhaps that would be the best method before heating with reflow gun ?

Install:
Hmmm, let me remove it first without collateral damage.....

Just to confirm:
https://www.digikey.com/product-detail/en/microchip-technology/ATSAM4S4BA-AU/ATSAM4S4BA-AU-ND/4557082

Is the one to order ?

Thank you

@dc42
Tried other cables, no difference.
Verified cable functionality by plugging up to an old Tom Tom, detected right away, so comms are goood.

U4 is putting out 3.26 V.

CA9 does have 3.26 at the end specified.

Either end of LA2 does show 1.19 V.

Nothing is getting hot.

Replacing the Atsam looks to be within my skilset, provided I can get one and it doesnt need extra programming with tools I may not have.
Digikey shows a few in stock, not sure if they would be exact matches.
https://www.digikey.com/products/en?keywords= ATSAM4S4B-AU

Will do.
I have brand new in the box Duet Wifi for the next project, the current cable I am using came out of that box to eliminate the possibility of of a bad cable.

I suppose I could try a few more different cables, have been using the one that came with the Duet Wifi boards.
Not really sure how to fully eliminate the USB port not making contact possibility. Plugging usb in does turn on the backlight, so at least GND, and 5V are getting through.

I will verify again the correct voltages later today. I was able to measure +3.3V yesterday in the spot I think you care referring to.

Did also measure 1.X voltage on a regulator, I forgot the exact number, will confirm later also.

Perhaps I described flashing incorrectly:
The backlight is on, always on, cant make it go off even with pressing erase for 1 second followed by reset.
What does, or did initially flash, is the screen itself. Every so often, I would say a 40 second average you would get a quick blip of the screen, kind of like the initial very short white illumination I normally get when powering on, just before the logo displays. Almost as if periodically the unit is trying to boot.

Ironically, I had a similar situation when I initially purchased the screen, before there were any motors or much else hooked up to it. When i was just familiarizing myself with the Duet Wifi and PanelDue I had just those two hooked together.
I was using the 10 pin ribbon cable at the time. Initially I had it hooked to the correct port via the ribbon cable, it came on and life was great.
Throughout the build process at one point I powered on an the screen did not boot. I believe that I had the 10 pin ribbon cable in the wrong port. Powered down, switched to the right port, and I think all was back to normal. Hard to remember, but what I do know is that it did not always boot the screen after that. Sometimes I had to boot a number of times, and I think I am correct in saying that sometimes the screen would boot after being powered for a while. Either way, that is when I initially got familiar with the process of flashing the firmware, bossa etc.
Was able to follow the guides, usb port came up at that time just as it should have, flashed without issue, booted without issue, switched over to 4 pin wire only since ribbon wasn't long enough to reach my desired location.
I put it in its case, and haven't touched it since. Have had no issues for the last 2 months, probably powered down and booted up 30 times since then.
About 2 weeks ago I did have an issue with the screen, or entire system rather going idle during a print. Screen would show IDLE on the corner while machine was still printing.
I originally thought it was on long prints, what would happen is that the screen would essentially stop getting new information, layer number would stop updating, etc.
The machine continued on, and the prints finished as expected. I do not know if pressing the stop button on the screen would have done anything at this point.
During this time the web interface could not connect either, I believe wifi was going idle.
Reboot would fix everything.
At the same time I was also having issues with Fusion 360 taking forever to launch, so I think all of it was really an issue caused by my router. Once I powered cycled it all was better, no more disconnection issues.
Don't know if much of that is helpful or not.
I was surprised that even if it is due to the router and wifi disconnecting that the screen would stop getting information and go idle.
So maybe there were some underlying issues, perhaps from once plugging the 10 pin ribbon into the wrong port.
Once i get my new screen I will be curious to see what happens if I turn off wifi router mid print.

Mike

@bearer

Yeah, based on not much more than a gut feeling I think it is going to be one of the micro controllers on the board.