Interesting to see the differences between the 2 kernels. Compared to my messages I found following lines in dmesg have disappeared with 3.5:
mtrr: type mismatch for e0000000,10000000 old: write-back new: write-combining [drm] MTRR allocation failed. Graphics performance may suffer. [drm:intel_dsm_platform_mux_info] *ERROR* MUX INFO call failed i915 0000:00:02.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16 i915 0000:00:02.0: restoring config space at offset 0xf (was 0x100, writing 0x10b) i915 0000:00:02.0: restoring config space at offset 0x1 (was 0x900007, writing 0x900407) i915 0000:00:02.0: setting latency timer to 64 while enabling RC6 states has been added: [drm] Enabling RC6 states: RC6 on, RC6p on, RC6pp off Probably a hint to the root cause? I also compared the BIOS settings: Javier has these options/settings: Integrated Graphics Share Memory [64MB] DVMT Memory [256MB] I only have: IGD DVMT Memory [256MB] (which I called previously "agp-aperture" - ancient name when PC's had a dedicated AGP-Port). This is the setting which I did change from "max" -> "256MB" and got my system stable - which still holds right now. However the "mtrr" setups (/proc/mtrr) are still identical with both kernels. Seems the "write-combining area" has become obsolete - or still not implemented in i915? Ingo -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org