Cables, drivers and screen resolution problem

I dual boot two PC between win10 and Linux mint 20 and use a KVM switch with DVI cables. Win 10 has no resolution issues whatever. But with Linux I can only produce a maximum resolution of 1600x900 with the more recent drivers such as 450 or 455. On the other hand if I use the 340 driver I can get 1920x1080 on one of my PCs which has an old GTX660 GPU. The other PC which has a GTX 1650 super does not have the old driver available for installation (presumably it wouldn’t work anyway.)
I notice that when using the more recent drivers if I look at display in preferences the monitor is not recognized. However using the old driver with the older PC or the Linux nouveau drivers it is. I think this is because the monitors EDID is not being found. Indeed the NVIDIA bug report shows the following "[ 47.125] (WW) NVIDIA(0): DFP-0 does not have an EDID, or its EDID does not contain a
[ 47.125] (WW) NVIDIA(0): maximum image size; cannot compute DPI from DFP-0’s EDID

I’m wondering if anyone else has this problem and if they do what a solution might be as 1920x1080 is preferable for both PCs if possible?

I have uploaded the NVIDIA bug report. If it’s not in the right format I apologize. Let me know and I’ll try to fix it

Regards Steve
.nvidia-bug-report.log (1018.4 KB) nvidia-bug-report.log.gz (217.7 KB)

Just to add to this, it turns out that if I remove the KVM switch and just use a single HDMI cable to one PC the new drivers will produce the 1920x1080 resolution I want. It is not the KVM switch itself however that is the problem. Using a single DVI cable with a single PC won’t produce the 1920x1080 resolution it’s still stuck at 1600x900. I’m thinking that if I switch all my cables and the KVM switch to HDMI that would solve the problem. However this problem doesn’t exist in windows so I’m perplexed as to why it’s a problem in Linux.

I can only presume that at some point NVIDIA changed the Linux drivers in such a way that for whatever reason they do not ‘like’ DVI connections. I’d really appreciate it if someone could suggest what they did and why.

Regards Steve