HDMI output to Dell 2007fpb monitor not working

Question

Hello,

I purchased an Element14 Raspberry Pi 3b+ in late November 2019. My plan was to use it in a retroPi type of setup, using a Dell 2007fpb monitor as the display. When I initially got the Pi I connected it to the monitor via a HDMI-DVI cable and it booted the image I had just fine. Everything looked good so I disconnected things until I was ready to really devote some time to doing the build. The next time I put things together - with zero changes to anything, other than cables having been disconnected and reconnected - I no longer got any output displaying on the monitor. I tried many different troubleshooting steps:

I was able to connect the Pi to a TV via HDMI and the output was fine.
I was able to connect it to another (newer) monitor via the same HDMI-DVI cable I originally used and everything worked fine.
I tried 3 different HDMI-DVI adapters with the 2007fpb, none worked
I tried reflashing the boot image, as well as trying different boot images. None worked
I tried an HDMI-VGA adapter with the 2007fpb, it didn't work
I tried editing the config.txt file as follows (note that I didn't have to do any of this when it was working the first time):
- I tried setting hdmi_safe in the config.txt file, it didn't work. This was re-commented out after verifying, so all subsequent testing was done with this turned off.
- I tried setting hdmi_force_hotplug in the config.txt file, it didn't work
- I tried setting various recommended combinations of hdmi_drive, hdmi_group, hdmi_mode, config_hdmi_boost, none worked
I read about people experiencing problems with the EDID being corrupted on the 2007fpb monitor, so I tried editing the config.txt file to ignore the EDID from the monitor and force a specific mode, but none worked (I tried all supported modes for the monitor)
I also read about sometimes more power being required so I upgraded to a 3A power supply (had been using 2.5A previously). No effect
At this point I assumed the monitor was somehow "bad", but when I connected it to a PC using the same HDMI-DVI cable it worked fine
Finally, I ordered another Element14 Raspberry Pi and hooked everything up again and everything worked fine.

This seems to suggest that something "happened" to the original Pi that I was using, but for the life of me I have no idea what since as mentioned HDMI output to other devices does work. Of course all the time I spent troubleshooting has put me beyond the return period for the original, so I'm stuck there. But now my main concern is understanding what happened because I'd like to ensure that the same thing doesn't happen again to the new Pi. Does anyone have any thoughts on what may have caused this problem? And even better, some way to fix it so my original can still be used?

Thanks

mp2100 · Answer

I have a way that you probably can use your original rPi, but you may not like it.

First of all, good troubleshooting and documenting your troubleshooting. I had a few suggestions half way through and then, oh, you tried that already.

So, I happen to have my own Dell 2007fbp monitor. It's an old model, I rescued it from the recycle pile. And I rescued it for use with an rPi because it has a composite port:

https://www.dell.com/downloads/emea/products/snp/UltraSharp%202007FP_EN.pdf

And all raspberry pi models have a composite port. Resolution won't be very good, but it would make your rPi usable. With the newer Pi models, it's a bit more difficult because you'll need a 3.5mm jack to composite cable.

.

cstanton · Answer

This sounds like it could be the victim of the order in which the devices are setup and powered on. For example: - Power off all devices - Connect up the cabling, except power. - Connect power to the display first, turn the monitor on into standby mode with only one display input - Power on the Raspberry Pi using a default Raspbian setup on the SDCard Raspbian in its latest builds have some accommodations for the display due to the dual output of the Raspberry Pi 4, it tries to detect how the screen works that it's connected to and determine the correct resolution and settings, and if it hasn't received this information as the Raspberry Pi is powered up/powered on, then it's going to have difficulty negotiating the display properly. I'd be interested if an older version of Raspbian would work 'better', though it may be difficult to find an older version these days. Still, my main thoughts here are the order in which the devices are plugged in and powered on. Equally if this has already been tried, then attempting to plug in the display when both the display and Raspberry Pi have been powered on separately may be worth trying, though I would suspect it may not renegotiate the connection to the display as well.

kse001 · Answer

Yes, that is correct. I can even add a little more information to that: I had gotten a second 2007fpb monitor and run through the tests on both of them after the original Pi stopped displaying, and neither one displayed. Both monitors exhibited the same behavior: they detected "something" was connected to the DVI port, but went into power saving mode and never came out. The same thing happened when I tried the HDMI-VGA adapter on both of them. From what I read in my research, this was common for others who have experienced this problem. I unfortunately no longer have access to the second monitor for testing, so I'm limited to testing with the first one which is connected (and still working!) to the second Pi.