Daisy-chaining on new PC not working

Hi,

I have a dual monitor set-up, both Lenovo P24h-10, monitor A being my 'main' monitor connected to either my work laptop via USB-C or my personal computer using DP. My secondary monitor, let's call it monitor B, is connected to monitor A via DP out.

Monitor B input is always set to DP and monitor A input is set to either USB-C or DP depending if I'm working or using my personal computer.

With my old PC, which had a GTX 1050, this set-up worked flawlessly. Once I'm done with work, I just switch the input on monitor A from USB-C to DP and voila, both monitors switch.

I recently got a new computer and I hoped it would be the same plug in the DP cable from monitor A and away we go. But this was not to be.

Neither of the DP 1.4a ports on the new graphics card would output a Singal to either monitors. Not even the onboard DP would output a signal.

The graphics driver was already up to date but I uninstalled and reinstalled the driver and same thing, nothing. I got a HDMI cable and connected monitor B to the PC and changed the input source, and only monitor B worked. Monitor A still had no output from the DP port.

I unplugged and replugged monitor A's DP into the other port on the graphics card and it returned a signal, but it was something still like 1024x768. There was no higher resolution to select from in the windows explorer display setting. I'd had to go into NVIDIA control panel to select the native 1440 resolution for monitor A.

I've tried with the other DP port on the graphics card and it works, so I can confirm that both DP port on the graphics card works. If I now switch input of monitor B from HDMI to DP (with this still connected to monitor A's DP out port). Monitor B outputs a signal in native resolution. HURRAY! Not so fast, if I switch monitor A's input to USB-C, to do work on my work laptop, and then back to DP. It SOMETIMES works as expected and sometimes no output at all on either monitors, I would have to then switch monitor B to HDMI, plug and unplug monitor A's DP cable etc. as above.

Even when the set up above works, windows think there are three monitors connected, 1 HDMI and 2 DP monitors (as they are daisy chained together), which is not ideal. I understand that I can just mirror the daisy chained monitors but that's not the point.

If I get the daisy-chain working (i.e. monitor A connected to PC using DP, monitor B connected monitor A using DP-out AND connected to PC with HDMI, but input source is DP). If I unplug the HDMI from the graphics card to mimic my original set-up with my old PC, both monitors go black, then back on with output, then black etc. Basically, flickering at a very low frequency, ~1-2 seconds.

Any help would be appreciated.

Kevin