started the pc... nothing happened... reset - then recovery mode ... then monitor frequeny "0" under settings/screen "screen unknown - default" 1920x1080 Frequency 0 Hz
that's one of these onboard graphic cards
lspci -nnk | grep -i "VGA|'Kern'|3D|Display" -A2 01:00.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset USB 3.1 XHCI Controller [1022:43d5] (rev 01) Subsystem: ASMedia Technology Inc. 400 Series Chipset USB 3.1 XHCI Controller [1b21:1142] Kernel driver in use: xhci_hcd
(yesterday everything worked fine as usual 
lspci -nnk | grep -i "VGA|'Kern'|3D|Display" -A2 01:00.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset USB 3.1 XHCI Controller [1022:43d5] (rev 01) Subsystem: ASMedia Technology Inc. 400 Series Chipset USB 3.1 XHCI Controller [1b21:1142] Kernel driver in use: xhci_hcd
don´t manage anyway to a step where I could change the monitor settings.../resp.. installing of new drivers
didn't find any at AMD either - only for Windows
//before with the old pc I had the same problem - only started after recovery mode - but then also USB did not work any more - so I bought a new pc presuming that the mainboard was just broke//
xandr tells me this
xrandr -r 75
Rate 75.00 Hz not available for this size
ubu@ubu-System-Product-Name:~$ xrandr --query
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 640 x 480, current 1920 x 1080, maximum 1920 x 1080
default connected 1920x1080+0+0 0mm x 0mm
1920x1080 0.00*
640x480 0.00
in which conf.log can I change the settings manually - but if I do it, won't that cause bigger problems ? ? /etc/conf ... again: just the frequency is nill which is very annoying
it is some ASUS IPS 17 inch