Third time's a charm?

I thought my troubles were behind me, but I failed at getting a parallel port to work on my MSI-based PC. The good news is that Best Buy actually agreed to refund my money for the Dell and I was able to replace it with a Lenovo desktop. The 2.8.2 .iso installs on the Lenovo, but won't subsequently boot and actually has the same exact issue with Iwlwifi9000 as the Dell. So here's the score card:

Dell Inspiron 3880: 2.8.2 installs, but won't boot
MSI 2.8.2 installs, but parallel port doesn't work
Lenovo: 2.8.2 installs, but won't boot

Unless someone has a better idea, I'm going to try to install Debian 10, add a RT_PREEMPT kernel and Linuxcnc. This is the start of week 2 of trying to install linuxcnc.
 

You really need to give more information regarding the MSI parallel port issue.
Unfortunately no one is a mind reader.
You haven't said whether the Parallell is on board, PCI or PCIe.
As much as forum members want to help, getting information from those wanting help can be like pulling, very painful & very slow.

Here's a thread about parallel ports.
forum.linuxcnc.org/18-computer/42826-par...-info-thread?start=0

So if you are willing & able to supply a bit more info the advice will be a lot better.

I haven't really given up on the parallel port option--today was just the last day I could return the dell (and super surprised they took it back). So I figured I would try the Lenovo and see where it leads.

I have three different parallel port cards. On the MSI, only one of them is detected during boot. I confirmed that with both dmesg and lspci -v. The correct parport directory structure is created with the correct entries for address and IRQ. It just never connects to the Gecko. I tried using the .hal parport tester and toggling those bits does not, for example turn on the charge pump on the Gecko. If the Lenovo doesn't work, I'll probably go back to that. But at least I have 45 days to mess around without losing money.

BTW: I am super grateful for the help I've received so far. Sorry if I sound a little jaded, but its been a little frustrating.

If you are installing on new hardware, I'd be leaning towards Debian 11 (non-free) and master branch compiled from source per the QTPYVCP instructions.

This will give you a later kernel for more chance of hardware support.
 

Does the Lenova boot from the usb using the iso? If so, the boot menu should have an option to boot to the hard drive. My Debian 11 ended up in this state at one point. I ended up repartitioning the hard drive (actually SSD), installing Windows in one partition (Required to run Clearpath servo configuration.) and LinuxCNC (with the LinuxCNC iso) on another. It dual boots now with no problems,

Using the parallel port tester for to activate a charge pump is completely useless, unless you have modified the Hal file to generate the correct frequency.
So if you are using the parallel port tester without modification trying to the trigger the charge pump is useless.
The parallel port tester generally relies on the user having a few LEDs and switches connected. Either via a BOB or simply connected directly to the port. Or you may choose to use a multimeter and a piece of wire.
So I would suggest you try and test the parallel port NOT by trying to trigger the charge pump. If the parallel is on board, undamaged, enabled in the bios and you are using the correct address it will work.

So this part is where I'm the most ignorant. Debian 10 is problematic on newer hardware. There are countless pages directed to this, and lots of people have the same exact issue that I'm seeing (blank screen after install and reboot). It's not easily solved. For that reason, Debian 11 is a much better choice. But that means that I have to use 2.9 (because 2.8 won't build on Debian 11). Is this likely to be less stable than 2.8?

One of the most confusing parts of linuxcnc is the dependency of versions on different linux distributions. I'm getting the sense that this is less of a concern (at least with RT_PREEMPT) and that almost any linux should work as long as the software builds. Does that seem accurate?

If you have the knowledge and persistence it will work on your favourite distro, you just need to install the required libraries.
This maybe from your distros package manager or building from source, which would be the case with Slackware.
2.9 is stable as far as I know, many are using it.