Yes, they are too powerful to go fanless.

I assembled the system i was talking about myself. In Spanish:
http://pedroreina.net/hardware/chus/
but if are not confident with hardware, may be wise to get help on this side or even order the system already assembled. Usually they charge around $50, you can ask a quote beforehand.

Agreed, of course. I would like to point out that Beowulf run perfectly on my 9th generation Intel i5-9600T with the stock kernel.

Could you see any error message before the prompt?

I know that you already installed it, but I would like to show a theme I did for webkit2 greeter:
http://pedroreina.net/desarrollos/tlwg/

I'm using it with Beowulf.

May be in expert mode you accidentaly skipped one screen. I did it sometimes and went to bizarre situations as you described. I prefer the expert method anyway, but sometimes a small error gives you trouble: just be aware.

In my experience, random behaviour is very often caused by faulty hardware.

The "-y" option is handy too.

I dislike "autoselecting". But I can select the non-HDMI output with ALSA configuring it. There are a lot of info about that.

It seems so:
https://dev1galaxy.org/viewtopic.php?pid=19495#p19495

I dont need VMWare since a lot time. In 2005 I had to buy a license because I did not find an alternative. Not needed anymore. YMMV.

I'm sorry. It seems to me that your install is kind of broken. Of course you can reinstall (I did it a couple of times years ago), no problem. But most likely it can be fixed.

The file /etc/apt/sources.list should be owned by root. Once that is fixed, you can try the commands that gdebi-gtk suggests.

I think that you are taking about the file virtualbox-6.1_6.1.16-140961~Debian~buster_amd64.deb. It should work on your Beowulf box. I have installed VB from deb archive a lot of times (not on Beowulf): it works, but you need to compile a few kernel modules afterward (there is an assistant for this). If the tildes on the name are a problem, just rename the file after download it again.

Also, you can find in this very forum options to VB. A lot of people here dislike VB and explain alternatives that can work for you.

Thank you. These are very good news. Very long term support can be very useful to people running old systems. Sure they have security concerns, but any sysadmin should know the risks. My point is that beeing able to apt install more packages in an old box is very convinient.

This is a very personal taste and a lot of people here are going to customize their environment. But we need a default. This one proposed pleased me very (VERY!) much.

Please note that your Debian Wheezy is using gphoto2 to access to the camera. May be you are missing some package related with gphoto2 in your new box.