[qubes-users] Xen causes kernel panic during install - USB boot

Have Qubes 4.0.3 on a USB created from a live linux image. The boot halts on the first screen. Can anybody see anything obvious in the boot screens that I could try and get this working?

Its a new high spec machine, with the new(ish) 10th Gen intel i7 10700 with the PRIME B460M mothernboard.

Thanks

Should add that this is using legacy mode boot, as using UEFI boot gives a security violation error message and will not proceed.

Commenting out:
noexitboot=1 mapbs=1 in teh bootx64.cfg file gets me further, but only as far as a black screen. I have tried setting console=none and that will not get past the UEFI loader.

Seems like I am stuck. Best guess at the moment is that it is not liking the Intel Integrated Graphics.