https://bugs.freedesktop.org/show_bug.cgi?id=110897
--- Comment #20 from cosiekvfj@o2.pl ---
I have less and less of an idea when this thing happens.
My first thought was maybe compositor or 64 vs 32 bit os. I'm using xfwm with compositing turned off. I also changed the CPU in this laptop ;) and I'm using 64 bit os.
*-cpu description: CPU product: Intel(R) Core(TM)2 CPU T5500 @ 1.66GHz vendor: Intel Corp. physical id: 4 bus info: cpu@0 slot: U23 size: 1666MHz capacity: 1667MHz width: 64 bits clock: 100MHz capabilities: fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx x86-64 constant_tsc arch_perfmon pebs bts rep_good nopl cpuid aperfmperf pni dtes64 monitor ds_cpl est tm2 ssse3 cx16 xtpr pdcm lahf_lm pti dtherm cpufreq
But after you told us that glxgears "magically" works sometimes for you then I have no idea.