problem installing recent 2.8.2 on HP dc7700

Hello,
I've tried to install LinuxCNC 2.8.2 on an old desktop machine HP dc7700 with Intel 6300 Core2Duo CPU @ 1.88 GHz.
The system boots from USB Memorystick and the Live system is running.
Installing completes network (found already that sometimes the stick hast to be removed and inserted again), then the partioning passes (but the formatting ext4 shows 33 % and then done). The next step, copying the files fails aways at about 7 %.
When I boot the live system again, I can see the hdd is mounted and showing some files and directories.
I've tried several HD options in the BIOS, none was working. The BIOS has a HDD check which passes positive. Previously, I had installed Ubuntu and that was running on this machine.
Any hints what can be checked further?

I have also a Raspberry Pi 4, I see that it is supported now also with LinuxCNC. Is that a better alternative to the stone old HP machine?

Thanks,
Jojo

the SSD (120 GB) gives the same problem at the same step, at 7 % of copying files. I have written the USB stick new with verify option.
The memory test ran also fine several times.

ok, got it. Using the 3rd USB stick was successfull. There were read errors reported in the syslog during installation, I could have read that earlier...
So far, the installation is really great.