7920 gives code 43 with all graphics cards in all PCIe slots

I couldn't find what model year your 7920 is.  Here's the Reference Guide to the Precision Workstation Diagnostic Indicators.

I'm sure you noticed, year made should be stamped on the inside of the cover and/or chassis.

If not already, make sure the size 2032 battery is new.

In the Owner's Manual:

4-3 4 amber blinks followed by a short pause, 3 white blinks, long pause, then repeats Bad Memory ● Memory VR would not turn on. Check Memory insertion

Sorry, my usage of 'code 43' was unclear.  Code 43 is seen in windows device manager when a device is having issues and windows stops it.  In this case, it's for my video card.

I'm not sure what model year my 7920 is.  I didn't see any date inside the case.  Is there a particular spot to look in?  I looked up the service tag number and can't find any date there either.

I measured the 2032 battery at 3V so it seems like it should be okay.

I tried installing a version of Linux with Nvidia drivers included.  This seemed to work fine.  The video card was reported as working correctly and when I ran a 3D benchmark to stress the card it ran at 100%, drawing the rated power and got up to around 70C.  So the hardware seems to work, but windows and Nvidia drivers seem to not work together with my hardware for some reason.  I've tried a few versions of windows 11 Pro today (2H23 and 2H22) with no improvements.

This is probably due to a driver issue. I am running an RTX A4500 on two machines, a T7910 (Windows 10 22H2) and a T5820 (Windows 11 23H2). Both are fine. I would do two things: first run sfc /scannow as administrator in command prompt, and second check the resources tab of your GPU for any conflicts.

It looks like windows 11 is the problem.  I installed windows 10 and everything works fine.

I'm glad, but I would still try to solve the Windows 11 issue. If it works for me, it should work for you as well. Besides, Windows 10 is nearing end of life (this year I believe).

I can probably throw windows 11 back on another drive to play with.  I did actually like how I had win 11 setup before I realized the video card wasn't working.  What would you do with the information from your suggestions if there are conflicts?

This machine will live almost entirely offline, so if I have to stick with windows 10, it's not that much of a negative to me as long as it works.  If it performs how I think it will, I'm hoping I can get 5-10 years of use out of it.

Also, is there a way to get notified via email of replies?  I can't find anything under profile settings to allow that.

To be honest, I prefer Windows 10 and will keep it as long as possible. What I also like to do is to image my C drive while it's fresh (including good drivers, etc). If anything goes wrong, I can then simply restore the system in a matter of minutes.

One other suggestion would be to download a bootable USB of Windows 11 from MS, and use it to upgrade from inside a running Windows 10 installation. It's much quicker. Good luck!

I really must rush, but should add that the Windows 11 USB upgrade can be done off-line. So to summarise:

1. Install Windows 10 + all drivers,

2. Image your installation,

3. Upgrade to Windows 11 off-line,

4. Activate if AOK,

5. Check online for updates,

6. Image again.

Bye!

Installed windows 11 on another drive, looked in device manager, graphics card under resources and it just says it's not using any resources because it has a problem.  Nothing else is there.  Running sfc /scannow, it said there were no integrity violations.

This is happening after the Windows 11 upgrade, as suggested? Open event viewer and see if any critical system events (red) are listed in the log. What are their ID’s?

Is your driver showing that it has been digitally signed? Windows 11 uses TPM 2.0 which is fussy about these things. If your RTX A2000 has had its BIOS flashed previously, to lower the voltage for example, Windows will refuse it with a code 43 error.

My A2000 is new, straight out of the box.  The driver is the most recent from Nvidia, 551.23.  The driver page in device manager looks the same as yours, except the driver date and version are newer.  The signer is the same.  I see this behavior with it not working in win 11 with a clean install or with an upgrade from a working win 10 install.  The driver remained the same across the upgrade but the card is disabled under windows 11.

In event viewer, I don't see anything marked critical, but I see some errors for Nvidia.  One is 'event provider Nvidia|NVWMI|EVENTS|2.0 attempted to register query "select * from SyncEvent" whose target class "SyncEvent" in //./ROOT/CIMV2/NV/Events namespace does not exist.  The query will be ignored.'

In device manager, on the A2000 window under events, if I click 'view all events', all the events it shows me in event viewer are marked 'information'.  They have event ID's of 430, 440, 20003, and 420.  They start off saying 'device requires further installation', then 'device settings migrated from previous OS installation', then 'Driver management has concluded the process to add service NVDisplay.ContainerLocalSystem for Device instance ID PCI... with the following status: 0.'  Then it says it deleted that device.  Then it says it requires further installation.  Then it says it concluded the process to add services a few more times.

My Windows 11 installation did not delete the NVDisplay.Container service like yours, if I understand you correctly. See the image below. That may be the cause of your problem. I still feel that this is a driver issue, and as a last resort either do a clean install of 551.23 (under custom install) or roll it back if you can. I use 528.49.