AMD Phenom II X4 945 - only 2 CPUs recognised

**yogurtu_ctes** · February 19th, 2010

Hi Everyone,
I'm having trouble with my ubuntu distro. I have a quad core CPU (AMD Phenom II X4 945), but it only uses two cores.
I'm using ubuntu karmic, fully up to date. I upgraded my BIOS yesterday to see if that is the problem.
My mother board is a Gigabyte GA-MA790FXT-UD5P

Here's my "dmesg | grep -i cpu":

[ 0.000000] Initializing cgroup subsys cpuset
[ 0.000000] Initializing cgroup subsys cpu
[ 0.000000] KERNEL supported cpus:
[ 0.000000] x86 PAT enabled: cpu 0, old 0x7040600070406, new 0x7010600070106
[ 0.000000] SMP: Allowing 4 CPUs, 2 hotplug CPUs
[ 0.000000] NR_CPUS:64 nr_cpumask_bits:64 nr_cpu_ids:4 nr_node_ids:1
[ 0.000000] PERCPU: Embedded 30 pages at ffff880028022000, static data 90720 bytes
[ 0.000000] Initializing CPU#0
[ 0.000000] SLUB: Genslabs=14, HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
[ 0.009146] HPET: 4 timers in total, 1 timers will be used for per-cpu timer
[ 0.011799] Initializing cgroup subsys cpuacct
[ 0.011814] CPU: L1 I Cache: 64K (64 bytes/line), D cache 64K (64 bytes/line)
[ 0.011816] CPU: L2 Cache: 512K (64 bytes/line)
[ 0.011818] CPU 0/0x0 -> Node 0
[ 0.011821] CPU: Physical Processor ID: 0
[ 0.011822] CPU: Processor Core ID: 0
[ 0.011824] mce: CPU supports 6 MCE banks
[ 0.125847] CPU0: AMD Phenom(tm) II X4 945 Processor stepping 02
[ 0.010000] Initializing CPU#1
[ 0.010000] CPU: L1 I Cache: 64K (64 bytes/line), D cache 64K (64 bytes/line)
[ 0.010000] CPU: L2 Cache: 512K (64 bytes/line)
[ 0.010000] CPU 1/0x1 -> Node 0
[ 0.010000] CPU: Physical Processor ID: 0
[ 0.010000] CPU: Processor Core ID: 1
[ 0.010000] mce: CPU supports 6 MCE banks
[ 0.010000] x86 PAT enabled: cpu 1, old 0x7040600070406, new 0x7010600070106
[ 0.280829] CPU1: AMD Phenom(tm) II X4 945 Processor stepping 02
[ 0.280835] checking TSC synchronization [CPU#0 -> CPU#1]: passed.
[ 0.290008] Brought up 2 CPUs
[ 0.290099] CPU0 attaching sched-domain:
[ 0.290106] CPU1 attaching sched-domain:
[ 0.500794] Switched to high resolution mode on CPU 1
[ 0.510018] Switched to high resolution mode on CPU 0
[ 0.710788] processor LNXCPU:00: registered as cooling_device0
[ 0.710816] processor LNXCPU:01: registered as cooling_device1
[ 1.350552] cpuidle: using governor ladder
[ 1.350553] cpuidle: using governor menu
[ 1.351358] powernow-k8: Found 1 AMD Phenom(tm) II X4 945 Processor processors (2 cpu cores) (version 2.20.00)
[ 23.773319] CPU0 attaching NULL sched-domain.
[ 23.773323] CPU1 attaching NULL sched-domain.
[ 23.811315] CPU0 attaching sched-domain:
[ 23.811324] CPU1 attaching sched-domain:

Here's my: "cat /proc/cpuinfo":

processor : 0
vendor_id : AuthenticAMD
cpu family : 16
model : 4
model name : AMD Phenom(tm) II X4 945 Processor
stepping : 2
cpu MHz : 3000.000
cache size : 512 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 5
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 pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc rep_good nonstop_tsc extd_apicid pni monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt
bogomips : 6042.58
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 48 bits physical, 48 bits virtual
power management: ts ttp tm stc 100mhzsteps hwpstate

processor : 1
vendor_id : AuthenticAMD
cpu family : 16
model : 4
model name : AMD Phenom(tm) II X4 945 Processor
stepping : 2
cpu MHz : 3000.000
cache size : 512 KB
physical id : 0
siblings : 2
core id : 1
cpu cores : 2
apicid : 1
initial apicid : 1
fpu : yes
fpu_exception : yes
cpuid level : 5
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 pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc rep_good nonstop_tsc extd_apicid pni monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt
bogomips : 6042.62
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 48 bits physical, 48 bits virtual
power management: ts ttp tm stc 100mhzsteps hwpstate

Please help

Thanks in advance