I can confirm this bug, it is also present on my machine: $ uname -a Linux unix 2.6.22-14-generic #1 SMP Tue Feb 12 07:42:25 UTC 2008 i686 GNU/Linux $ top top - 21:01:54 up 1 day, 1:15, 5 users, load average: 0.74, 0.78, 0.71 Tasks: 173 total, 2 running, 171 sleeping, 0 stopped, 0 zombie Cpu(s): 1.2%us, 3.5%sy, 0.1%ni, 94.0%id, 0.2%wa, 0.3%hi, 0.7%si, 0.0%st Mem: 2075944k total, 2022020k used, 53924k free, 9652k buffers Swap: 3911788k total, 360k used, 3911428k free, 1621568k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 7 root 34 19 0 0 0 S 10 0.0 110:01.04 ksoftirqd/1 8752 david 15 0 172m 55m 30m S 2 2.7 2:01.76 amarokapp 20844 david 15 0 2488 1100 792 R 2 0.1 0:00.01 top 1 root 18 0 2952 1852 532 S 0 0.1 0:01.31 init 2 root 12 -5 0 0 0 S 0 0.0 0:00.00 kthreadd 3 root RT -5 0 0 0 S 0 0.0 0:00.00 migration/0 4 root 34 19 0 0 0 S 0 0.0 0:01.88 ksoftirqd/0 5 root RT -5 0 0 0 S 0 0.0 0:00.00 watchdog/0 6 root RT -5 0 0 0 S 0 0.0 0:00.00 migration/1 8 root RT -5 0 0 0 S 0 0.0 0:00.00 watchdog/1 9 root 10 -5 0 0 0 S 0 0.0 0:00.02 events/0 10 root 10 -5 0 0 0 S 0 0.0 0:00.00 events/1 11 root 20 -5 0 0 0 S 0 0.0 0:00.00 khelper 31 root 10 -5 0 0 0 S 0 0.0 0:00.02 kblockd/0 32 root 11 -5 0 0 0 S 0 0.0 0:00.00 kblockd/1 $ cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 15 model : 35 model name : AMD Athlon(tm) 64 X2 Dual Core Processor 4400+ stepping : 2 cpu MHz : 2310.556 cache size : 1024 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 2 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt lm 3dnowext 3dnow pni lahf_lm cmp_legacy ts fid vid ttp bogomips : 4623.99 clflush size : 64 processor : 1 vendor_id : AuthenticAMD cpu family : 15 model : 35 model name : AMD Athlon(tm) 64 X2 Dual Core Processor 4400+ stepping : 2 cpu MHz : 2310.556 cache size : 1024 KB physical id : 0 siblings : 2 core id : 1 cpu cores : 2 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt lm 3dnowext 3dnow pni lahf_lm cmp_legacy ts fid vid ttp bogomips : 4621.35 clflush size : 64 $ cat /proc/interrupts CPU0 CPU1 0: 145 0 XT-PIC-XT timer 1: 0 2 XT-PIC-XT i8042 2: 0 0 XT-PIC-XT cascade 3: 74007 17032 XT-PIC-XT nvidia 4: 93611 19142 XT-PIC-XT EMU10K1 5: 4565754 766336 XT-PIC-XT sata_nv, ohci1394, cx88[0], nvidia 8: 2 1 XT-PIC-XT rtc 9: 0 0 XT-PIC-XT acpi 10: 25544 5179 XT-PIC-XT ohci_hcd:usb2 11: 3021120 553172 XT-PIC-XT ehci_hcd:usb1, sata_nv 12: 28662946 12905374 XT-PIC-XT eth0 14: 707706 111242 XT-PIC-XT ide0 NMI: 0 0 LOC: 29042798 24486198 ERR: 51528518 MIS: 0 $ lsmod Module Size Used by cdc_ether 7168 0 usbnet 19976 1 cdc_ether cdc_acm 17184 0 mii 6528 1 usbnet xt_TCPMSS 5888 1 xt_tcpmss 3200 1 xt_tcpudp 4224 1 iptable_mangle 3840 1 ip_tables 13924 1 iptable_mangle x_tables 16260 4 xt_TCPMSS,xt_tcpmss,xt_tcpudp,ip_tables pppoe 15680 2 pppox 4872 1 pppoe ppp_generic 29332 6 pppoe,pppox slhc 7552 1 ppp_generic snd_rtctimer 4384 1 binfmt_misc 12936 1 rfcomm 42136 2 l2cap 26240 11 rfcomm bluetooth 57060 4 rfcomm,l2cap nfsd 220912 13 exportfs 7040 1 nfsd lockd 67592 2 nfsd sunrpc 172412 8 nfsd,lockd cpufreq_userspace 5280 0 cpufreq_ondemand 9612 0 cpufreq_powersave 2688 0 cpufreq_stats 7232 0 freq_table 5792 2 cpufreq_ondemand,cpufreq_stats cpufreq_conservative 8072 0 container 5504 0 dock 10656 0 sbs 19592 0 video 18060 0 ac 6148 0 button 8976 0 battery 11012 0 ipv6 273892 16 sbp2 24072 0 parport_pc 37412 0 lp 12580 0 parport 37448 2 parport_pc,lp snd_emu10k1_synth 8192 0 snd_emux_synth 35456 1 snd_emu10k1_synth snd_seq_virmidi 8064 1 snd_emux_synth snd_seq_midi_emul 7680 1 snd_emux_synth snd_emu10k1 137248 4 snd_emu10k1_synth snd_ac97_codec 100644 1 snd_emu10k1 ac97_bus 3200 1 snd_ac97_codec snd_pcm_oss 44672 0 snd_mixer_oss 17664 1 snd_pcm_oss snd_pcm 80388 4 snd_emu10k1,snd_ac97_codec,snd_pcm_oss snd_page_alloc 11400 2 snd_emu10k1,snd_pcm snd_util_mem 5760 2 snd_emux_synth,snd_emu10k1 snd_hwdep 10244 2 snd_emux_synth,snd_emu10k1 tuner 63144 0 snd_seq_dummy 4740 0 snd_seq_oss 33152 0 joydev 11328 0 snd_seq_midi 9600 0 snd_rawmidi 25728 3 snd_seq_virmidi,snd_emu10k1,snd_seq_midi cx8800 34944 0 cx88xx 68132 1 cx8800 snd_seq_midi_event 8448 3 snd_seq_virmidi,snd_seq_oss,snd_seq_midi snd_seq 53232 10 snd_emux_synth,snd_seq_virmidi,snd_seq_midi_emul,snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_seq_midi_event snd_timer 24324 4 snd_rtctimer,snd_emu10k1,snd_pcm,snd_seq snd_seq_device 9228 8 snd_emu10k1_synth,snd_emux_synth,snd_emu10k1,snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_rawmidi,snd_seq pcspkr 4224 0 af_packet 24840 4 ir_common 35460 1 cx88xx xpad 9988 0 nvidia 7822336 40 ide_cd 32672 0 cdrom 37536 1 ide_cd agpgart 35016 1 nvidia i2c_algo_bit 7428 1 cx88xx video_buf 26244 2 cx8800,cx88xx tveeprom 16784 1 cx88xx videodev 29312 2 cx8800,cx88xx v4l1_compat 15364 1 videodev compat_ioctl32 2304 1 cx8800 v4l2_common 18432 4 tuner,cx8800,cx88xx,videodev btcx_risc 5896 2 cx8800,cx88xx usbhid 29536 0 hid 28928 1 usbhid snd 54660 19 snd_emux_synth,snd_seq_virmidi,snd_emu10k1,snd_ac97_codec,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_hwdep,snd_seq_oss,snd_rawmidi,snd_seq,snd_timer,snd_seq_device k8temp 6656 0 emu10k1_gp 4736 0 gameport 16776 2 emu10k1_gp soundcore 8800 1 snd shpchp 34580 0 pci_hotplug 32704 1 shpchp i2c_nforce2 7040 0 i2c_core 26112 6 tuner,cx88xx,nvidia,i2c_algo_bit,tveeprom,i2c_nforce2 evdev 11136 6 usb_storage 73024 0 ext3 133896 2 jbd 60456 1 ext3 mbcache 9732 1 ext3 sg 36764 0 sd_mod 30336 5 ata_generic 8452 0 libusual 18448 1 usb_storage r8169 32260 0 ohci1394 36528 0 ieee1394 96312 2 sbp2,ohci1394 amd74xx 15260 0 [permanent] ide_core 116804 3 ide_cd,usb_storage,amd74xx sata_nv 20612 3 libata 125168 2 ata_generic,sata_nv scsi_mod 147084 5 sbp2,usb_storage,sg,sd_mod,libata ohci_hcd 22916 0 ehci_hcd 36492 0 usbcore 138632 10 cdc_ether,usbnet,cdc_acm,xpad,usbhid,usb_storage,libusual,ohci_hcd,ehci_hcd thermal 14344 0 processor 32072 1 thermal fan 5764 0 fuse 47124 1 apparmor 40728 0 commoncap 8320 1 apparmor $ lspci 00:00.0 Memory controller: nVidia Corporation CK804 Memory Controller (rev a3) 00:01.0 ISA bridge: nVidia Corporation CK804 ISA Bridge (rev f3) 00:01.1 SMBus: nVidia Corporation CK804 SMBus (rev a2) 00:02.0 USB Controller: nVidia Corporation CK804 USB Controller (rev a2) 00:02.1 USB Controller: nVidia Corporation CK804 USB Controller (rev a3) 00:06.0 IDE interface: nVidia Corporation CK804 IDE (rev f2) 00:07.0 IDE interface: nVidia Corporation CK804 Serial ATA Controller (rev f3) 00:08.0 IDE interface: nVidia Corporation CK804 Serial ATA Controller (rev f3) 00:09.0 PCI bridge: nVidia Corporation CK804 PCI Bridge (rev f2) 00:0b.0 PCI bridge: nVidia Corporation CK804 PCIE Bridge (rev f3) 00:0c.0 PCI bridge: nVidia Corporation CK804 PCIE Bridge (rev f3) 00:0d.0 PCI bridge: nVidia Corporation CK804 PCIE Bridge (rev f3) 00:0e.0 PCI bridge: nVidia Corporation CK804 PCIE Bridge (rev a3) 00:18.0 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] HyperTransport Technology Configuration 00:18.1 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Address Map 00:18.2 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] DRAM Controller 00:18.3 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Miscellaneous Control 01:00.0 VGA compatible controller: nVidia Corporation G70 [GeForce 7800 GTX] (rev a1) 02:00.0 VGA compatible controller: nVidia Corporation G70 [GeForce 7800 GTX] (rev a1) 05:06.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8169 Gigabit Ethernet (rev 10) 05:07.0 Multimedia audio controller: Creative Labs SB Audigy (rev 04) 05:07.1 Input device controller: Creative Labs SB Audigy Game Port (rev 04) 05:07.2 FireWire (IEEE 1394): Creative Labs SB Audigy FireWire Port (rev 04) 05:08.0 Multimedia video controller: Conexant CX23880/1/2/3 PCI Video and Audio Decoder (rev 05) I've booted with irqfixup, which seems to help a little bit but does not take the problem away. irqpoll just totally makes the machine unusable. I think that it is the Leadtek Winfast 2000XP Expert card causing the problem: $ dmesg | grep -i winfast [ 13.456000] CORE cx88[0]: subsystem: 107d:6611, board: Leadtek Winfast 2000XP Expert [card=5,autodetected] [ 13.600000] cx88[0]: Leadtek Winfast 2000XP Expert config: tuner=38, eeprom[0]=0x01 [ 13.600000] input: cx88 IR (Leadtek Winfast 2000XP as /class/input/input6 Let me know if there is anything I can help with to verify this bug..