Apologies for reposting: I hadn't ticked the 'notify' button.

Code: Select all

 > inxi -v3 -c5
System:    Host: Tui Kernel: 4.4.0-124-generic x86_64 (64 bit, gcc: 4.8.4)
           Desktop: KDE 4.14.2 (Qt 4.8.6) Distro: Linux Mint 17.2 Rafaela
Machine:   Mobo: ASUSTeK model: M5A97 version: Rev 1.xx Bios: American Megatrends version: 0705 date: 08/22/2011
CPU:       Hexa core AMD FX-6100 Six-Core (-MCP-) cache: 12288 KB flags: (lm nx sse sse2 sse3 sse4_1 sse4_2 sse4a ssse3 svm) bmips: 39733
           Clock Speeds: 1: 1400.00 MHz 2: 1400.00 MHz 3: 1400.00 MHz 4: 2400.00 MHz 5: 1400.00 MHz 6: 3300.00 MHz
Graphics:  Card: NVIDIA GK208 [GeForce GT 730] bus-ID: 01:00.0
           X.Org: 1.15.1 drivers: nvidia (unloaded: fbdev,vesa,nouveau) Resolution: 1920x1080@60.0hz
           GLX Renderer: GeForce GT 730/PCIe/SSE2 GLX Version: 4.4.0 NVIDIA 340.107 Direct Rendering: Yes
Network:   Card: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller
           driver: r8169 ver: 2.3LK-NAPI port: d000 bus-ID: 02:00.0
           IF: eth0 state: up speed: 100 Mbps duplex: full mac: 54:04:a6:26:11:9f
Drives:    HDD Total Size: 1160.2GB (28.9% used) 1: model: SAMSUNG_HD161HJ
           2: model: ST1000DM003
Info:      Processes: 299 Uptime: 6 days Memory: 4519.1/7930.2MB Runlevel: 2 Gcc sys: 4.8.4
           Client: Shell (bash 4.3.11) inxi: 1.9.17


and

Code: Select all

> xdpyinfo | grep -B2 resolution
screen #0:
  dimensions:    1920x1080 pixels (483x272 millimeters)
  resolution:    101x101 dots per inch


This works when a user is set up, but after some use, the dpi changed itself (maybe when I inadvertently bumped the Windows key and something else) so that the dpi decreased to something like 90 which results in insufficient screen to fit all the pixels into the display. That makes it unusable since most of the time the mouse cursor is invisible and the display moves at every mouse movement..

I can create a new user which uses the default settings which is fine. That led me to suspect a file in ~/.kde/ was different. After a lot of experimenting, I renamed some hidden files in ~/ which resulted in losing my customizations, but at least the dpi was correct and I could reset my customizing. Very unsubtle, but it worked. ... temporarily.

After a month, it happened again but my crude tinkerings didn't work. I need a proper fix.

I see in ~/.kde/share/config there are a lot of rc files, but I couldn't find anything that looked hopeful. I can't find any mention of such a happening anywhere on the internet, but someone must have experienced something similar. I had a similar problem with a VM on my work machine which disappeared when I swapped the screen for an identical one.

So, I'm totally mystified.

Any suggestions greatly appreciated.