Sparky 6.1 Qt hangs on old non-UEFI DELL XPS 501x (found workaround)

[nevertheless]

Trying to install Sparky 6.1 Qt, on an old 2010-era Dell XPS L501X, no UEFI support[1]. I have installed (using the same USB flash media) on another old machine. It has UEFI, if that matters. * During boot of USB flash install media, it hangs with a black screen & 1 line displayed: "ACPI Error: Evaluating _BCM failed (20200925/video-357)".

I rebooted & tab-key on the default grub entry, remove "quiet" (enter to continue). Then it hangs on a screen filled with lines, the last one saying: "Begin: Running /scripts/init-premount".

I rebooted & choose "failsafe" grub entry. That booted the Live desktop. I was able to install successfully.

* Post-install boot. Same problem as above. (1. Normal boot hangs with ACPI error. 2. Remove "quiet" hangs on "init-premount.").

However, instead of "failsafe" (I don't think that's an option after install), I edited ("e") the menu entry again, and removed both "quiet" & "splash" (ctrl-x to continue). The installed OS booted fine. (I've since found this works  booting the install media too, instead of "failsafe.").

I wanted to report this in case it's a bug that can be improved for others. Or, maybe there's a better way around this than what I found?

[EDIT: Apparently deleting "splash" only works ("quiet" is ok.). Googling, I found "nomodeset" (added to "quiet splash") is often recommended. But, when I used it, my desktop's resolution/aspect ratio wasn't right. Maybe I could have manually set this. But, deleting "splash" seemed to work well enough. I didn't use nomodeset.).]

[1] Dell XPS L501X (circa 2010. Old, pre-UEFI bios. It is up-to-date with Dell's latest bios version.)
CPU: 2nd Gen Core i5-560M 2.66ghz
Chipset: Intel HM55 Express
Video: NVIDIA GeForce GT 420M 1GB graphics with Optimus
Wireless: Intel Centrino Advanced-N 6200
Mem: 8g
HDD: SATA-1