Missing one CPU core

boinc · #1 15th December 2011, 08:28 PM

Hello,

Just install Fedora Core 16 on a new machine with a AMD Phenom(tm) II X4 965 Processor, but when I look at /proc/cpuinfo I see only three cpu cores. Seems like one is gone.

Is there anything in the OS that could cause this or is it (as I fear) the CPU that has one broken core?

RHamel · #2 15th December 2011, 10:31 PM

Does the GUI system monitor show only 3 cores?

stevea · #3 15th December 2011, 10:49 PM

Do these show some LNXCPU:00 type entries ?

ls -ld /sys/devices/*/*CPU*
ls -l /sys/bus/acpi/drivers/processor/

If those don't show 4 cpu entries 00, 01, 02, 03 - then look for a problem in
dmesg | less

Gödel · #4 15th December 2011, 11:03 PM

the cores are numbered 0 - 3 , are you sure you're counting correctly ?

boinc · #5 16th December 2011, 06:11 AM

From /var/log/messages:

Quote:

Dec 16 19:58:45 obi-wan kernel: [ 0.020638] CPU0: AMD Phenom(tm) II X4 965 Processor stepping 03
Dec 16 19:58:45 obi-wan kernel: [ 0.020998] Performance Events: AMD PMU driver.
Dec 16 19:58:45 obi-wan kernel: [ 0.020998] ... version: 0
Dec 16 19:58:45 obi-wan kernel: [ 0.020998] ... bit width: 48
Dec 16 19:58:45 obi-wan kernel: [ 0.020998] ... generic registers: 4
Dec 16 19:58:45 obi-wan kernel: [ 0.020998] ... value mask: 0000ffffffffffff
Dec 16 19:58:45 obi-wan kernel: [ 0.020998] ... max period: 00007fffffffffff
Dec 16 19:58:45 obi-wan kernel: [ 0.020998] ... fixed-purpose events: 0
Dec 16 19:58:45 obi-wan kernel: [ 0.020998] ... event mask: 000000000000000f
Dec 16 19:58:45 obi-wan kernel: [ 0.020998] NMI watchdog enabled, takes one hw-pmu counter.
Dec 16 19:58:45 obi-wan kernel: [ 0.020998] Booting Node 0, Processors #1
Dec 16 19:58:45 obi-wan kernel: [ 0.092007] NMI watchdog enabled, takes one hw-pmu counter.
Dec 16 19:58:45 obi-wan kernel: [ 0.092069] #2
Dec 16 19:58:45 obi-wan kernel: [ 0.163998] NMI watchdog enabled, takes one hw-pmu counter.
Dec 16 19:58:45 obi-wan kernel: [ 0.164012] Brought up 3 CPUs
Dec 16 19:58:45 obi-wan kernel: [ 0.164014] Total of 3 processors activated (20467.48 BogoMIPS).

Also Seti does not see more than 3 core's.

I'll try those commands stevea have suggested later (have to go to work now).

Gödel · #6 16th December 2011, 12:29 PM

Possibly a bios setting has changed?

http://www.tomshardware.co.uk/forum/...tivated-phenom

Sagitter · #7 16th December 2011, 12:46 PM

Quote:

Originally Posted by boinc

Hello,

Just install Fedora Core 16 on a new machine with a AMD Phenom(tm) II X4 965 Processor, but when I look at /proc/cpuinfo I see only three cpu cores. Seems like one is gone.

Is there anything in the OS that could cause this or is it (as I fear) the CPU that has one broken core?

Please show us the /etc/default/grub content in Fedora ~~Core~~ 16.

PabloTwo · #8 16th December 2011, 07:26 PM

Are you sure you have a Phenom(tm) II x4 and not a Phenom(tm) II x3 ? How trustworthy is the vendor you bought the new machine from, or the cpu part to build it? It's not unknown for unscrupulous vendors to pull the old switcheroo on parts, even relabelling them to appear to be something they are not.
Check out Wikipedia AMD