Red Hat Bugzilla – Bug 244030
powernow-K8 doesn't load on MP systems
Last modified: 2007-11-30 17:12:07 EST
Description of problem: powernow-K8 doesn't load on MP systems, and power
consumption thus becames (too) high.
Version-Release number of selected component (if applicable):
kernel 2.6.20-1.2952.fc6. Has been around since I changed mobo, before FC6 was
How reproducible: Always at boot time.
Steps to Reproduce:
1. Boot FC6 on my Asus M2N32 WS Pro mobo
2. See dmesg log "powernow-k8: MP Systems not supported by PSB BIOS structure"
Actual results: CPU always runs at max speed, Error dialogs when starting Gnome UI.
Expected results: powernow-K8 running, decreased CPU speed when applicable,
decreased pwer consumption.
Additional info: This is basically a bug in the Asus BIOS. However, it seems
unlikely that it ever will be fixed, and we thus might be forced to live with it.
Hw: Asus M2N32 WS pro CPU: : AMD Athlon(tm) 64 X2 Dual Core Processor 4200+
BIOS: Asus firmware 1102
Possibly a dup to bug 185578, reported against RH4.
I'm also seeing this error ('powernow-k8: MP systems not supported by PSB BIOS
structure') on every boot up of a Dell Inspiron 531s, Athlon 64 X2. I'm running
RHEL5 at the moment.
Would love to help test any fix. I really don't need to be running full out all
the time. Waste of energy and it generates a lot of heat.
Found the solution in the BIOS (Dell Inspiron 531s). It's not in the power
section, it's under Advanced / CPU Configuration / AMD Cool'n'Quiet Function.
It ships in the disabled state, for some reason, but when enabled the powernow
seems to load correctly.
I suppose this is assigned on kdnssd-avahi by mistake. Changing component to
This is almost certainly a BIOS bug.