After hibernating the computer today, same problem ! Here is the /proc/cpuinfo:
processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 23 model name : Intel(R) Core(TM)2 Quad CPU Q9550 @ 2.83GHz stepping : 10 cpu MHz : 2833.000 cache size : 6144 KB physical id : 0 siblings : 1 core id : 0 cpu cores : 1 apicid : 0 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 13 wp : yes flags : fpu 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 lm constant_tsc arch_perfmon pebs bts rep_good nopl aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 xsave lahf_lm dts tpr_shadow vnmi flexpriority bogomips : 5651.83 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: And /proc/interrupts CPU0 0: 137 IO-APIC-edge timer 1: 2 IO-APIC-edge i8042 4: 2 IO-APIC-edge 7: 1 IO-APIC-edge parport0 8: 0 IO-APIC-edge rtc0 9: 0 IO-APIC-fasteoi acpi 12: 4 IO-APIC-edge i8042 16: 499332 IO-APIC-fasteoi uhci_hcd:usb3 17: 22657 IO-APIC-fasteoi uhci_hcd:usb4, uhci_hcd:usb7 18: 113 IO-APIC-fasteoi ata_generic, uhci_hcd:usb8, ath 22: 7918 IO-APIC-fasteoi ehci_hcd:usb1, uhci_hcd:usb5 23: 1815402 IO-APIC-fasteoi ehci_hcd:usb2, uhci_hcd:usb6 40: 9341920 HPET_MSI-edge hpet2 42: 2 HPET_MSI-edge 43: 5 HPET_MSI-edge 48: 868500 PCI-MSI-edge ahci 49: 1635787 PCI-MSI-edge eth1 50: 1681680 PCI-MSI-edge i915 51: 924 PCI-MSI-edge hda_intel NMI: 0 Non-maskable interrupts LOC: 374 Local timer interrupts SPU: 0 Spurious interrupts PMI: 0 Performance monitoring interrupts IWI: 0 IRQ work interrupts RES: 53799 Rescheduling interrupts CAL: 42382 Function call interrupts TLB: 44245 TLB shootdowns TRM: 0 Thermal event interrupts THR: 0 Threshold APIC interrupts MCE: 0 Machine check exceptions MCP: 108 Machine check polls ERR: 13 MIS: 0 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/785220 Title: Only one CPU core wakes up from sleep To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/785220/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs