I'm having the same problem on an up to date 15.10. Only I cannot log back in because there's no display manager present. I can switch to a virtual console and there it works. But when I get back to Console #7 the display goes into power saving mode. The only trace from the crash is in dmesg:
kactivitymanage[1629]: segfault at 18 ip 00007f4cf6438e90 sp 00007ffead511e28 error 4 in libqxcb.so[7f4cf640a000+b5000]
krunner[2159]: segfault at 18 ip 00007f3523ebede8 sp 00007ffeb62663c0 error 4 in libqxcb.so[7f3523e75000+b5000]
kwin_x11[2164]: segfault at 18 ip 00007f6e63b14de8 sp 00007fff87859850 error 4 in libqxcb.so[7f6e63acb000+b5000]
plasmashell[2167]: segfault at 18 ip 00007f192ad04de8 sp 00007ffc222dd470 error 4 in libqxcb.so[7f192acbb000+b5000]
klauncher[2176]: segfault at 18 ip 00007fb52e3abde8 sp 00007ffda395b150 error 4 in libqxcb.so[7fb52e362000+b5000]
Over DVI it works fine - I can switch my display off and on again without problems. I have a Z87 MB with Pentium G3258 using the integrated graphics of the CPU.
I'm having the same problem on an up to date 15.10. Only I cannot log back in because there's no display manager present. I can switch to a virtual console and there it works. But when I get back to Console #7 the display goes into power saving mode. The only trace from the crash is in dmesg:
kactivitymanage [1629]: segfault at 18 ip 00007f4cf6438e90 sp 00007ffead511e28 error 4 in libqxcb. so[7f4cf640a000 +b5000] so[7f3523e75000 +b5000] so[7f6e63acb000 +b5000] so[7f192acbb000 +b5000] so[7fb52e362000 +b5000]
krunner[2159]: segfault at 18 ip 00007f3523ebede8 sp 00007ffeb62663c0 error 4 in libqxcb.
kwin_x11[2164]: segfault at 18 ip 00007f6e63b14de8 sp 00007fff87859850 error 4 in libqxcb.
plasmashell[2167]: segfault at 18 ip 00007f192ad04de8 sp 00007ffc222dd470 error 4 in libqxcb.
klauncher[2176]: segfault at 18 ip 00007fb52e3abde8 sp 00007ffda395b150 error 4 in libqxcb.
Over DVI it works fine - I can switch my display off and on again without problems. I have a Z87 MB with Pentium G3258 using the integrated graphics of the CPU.