My current setup:
ASUS Prime X470 Pro
Samsung 960 EVO Series PCIe NVMe - M.2 SSD (LVM encrypted)
Nvidia Quadro NVS 295 PCIe x1
AMD Ryzen 7 Series CPU
This setup works perfectly ok except in the graphic department. It's a little "slow".
I had gotten a Nvidia 8800 GTS SSC Edition 640MB card from a friend to replace it. The card works perfectly fine under his Windows setup. Linux. Not so much.
Doing the research, this card and my current card both use the same Nvidia driver (340.107). I went the route of just installing the new card but I get the following message during boot:
WARNING: Failed to connect to lvmetad. Falling back to device scanning. Volume group "ubuntu-vg" not found Cannot process volume group ubuntu-vg WARNING: Failed to connect to lvmetad. Falling back to device scanning. Reading all physical volumes. This may take a while... Found volume group "ubuntu-vg" using metadata type lvm2 WARNING: failed to connect to lvmetad. Falling back to device scanning. 2 logical volume(s) in volume group "ubuntu-vg" now active /dev/mapper/ubuntu--vg-root: clean, 401546/60907520 files, 8689639/243620864 blocks
Installing the NVS 295 back in allows the system to boot properly.
For kicks, I uninstalled the 340 drivers and installed the 390 drivers. While it did allow the system to boot, it did not work out as I had hoped. Only one monitor worked and it was limited to 1024x768.
I tried uninstalling the video drivers but when I rebooted I got the following: green dots scattered on a black background
I tried booting up with just one monitor connected (and no drivers installed) and it went to a black screen.
Output from lsmod while booted in recovery mode:
nvidia_uvm 36864 0 nvidia 10559488 1 nvidia_uvm drm 401408 2 nvidia
Tech info on the card per the system:
VGA compatible controller: NVIDIA Corporation G80 [GeForce 8800 GTS] (rev a2) (prog-if 00 [VGA controller]) Subsystem: eVga.com Corp. G80 [GeForce 8800 GTS] Flags: bus master, fast devsel, latency 0, IRQ 86 Memory at f6000000 (32-bin, non-prefetchable) [size=16M] Memory at e0000000 (64-bit, prefetchable) [size=256M] Memory at f4000000 (64-bit, non-prefetchable) [size=32] I/O ports at d000 [size=120] [virtual] Expansion ROM at 000c0000 [disabled] [size=128k] Capabilities:  Power Management version 2 Capabilities:  MSI: Enable- Count=1/1 Maskable- 64bit+ Capabilities:  Express Endpoint, MSI 00 Capabilities:  Virtual Channel Capabilities:  Power Budgeting <?> Kernel driver in use: nvidia Kernel modules: nvidiafb, nouveau, nvidia
I did see some steps in How to install nvidia driver with secure boot enabled? but I wasn't sure if they may be applicable so, in order to not cause unintended harm, I haven't followed them.
Any ideas on how to get this to work? All of the other questions here don't seem to help solve the problem.