[linux-audio-user] CPU clock - beware

Matthew Barber brbrofsvl at aol.com
Wed Jul 21 02:23:56 EDT 2004

This might not be an appropriate place to ask this question, but I've
gotten help here before on a number of things...

So I have an Athlon XP 2500+ and a DFI motherboard with the nvidia
nforce2 chipset.  I have run it for almost a year, and it has been rock
solid under linux (not as much under Windows), red hat 9 and planet
ccrma kernel/drivers/software -- 2.4.26-1.ll.rh90.ccrma.  RME hdsp
multiface, and um... 2x512MB Crucial unbuffered DDR400.  Great, except -
I have never been able to set the appropriate bus clock in the BIOS
without linux becoming COMPLETELY unstable.  If I set it to the
published specs (166Mhz bus, x11 multiplier == 1.83Ghz), I usually can't
even get through the linux boot process; if it makes it through the boot
process, it will usually hang at the NVIDIA screen, or at the signin...
if it makes it past that, I can sign in, do a few things in a shell, but
then after about 2 minutes at most, the system freezes.  And we're
talking about a hard freeze - no ctl-alt-del, no ctl-alt-backspace, no
response at all.  Windows runs as fine as it ever has.  The only way I
can get linux to run stably is to underclock the system at 100Mhz, which
puts my CPU clock at a wimpy 1.1Ghz.  Setting the multiplier higher than
11 but maintaining the 100Mhz bus clock results in the same problem.  I
thought for a moment that the memory clock and the bus clock weren't
syncing, so I set them in 1:1 ratio - linux still hates it at any
frequency.  You can lock AGP at 66Mhz, still nothing doing.  This is a
board and proc combo that has been renowned for mega overclocking - I
shouldn't have to underclock it to have things run right.  Windows runs
fine so I'm wondering if it's not a problem in my kernel or distro
rather than the bios or hardware.  I have not as yet tried to boot
another kernel, but I will tomorrow when my mind is clear (I just
started trying to fix it today, and I'm weary).  Any ideas about it, or
about where I could read to fix it?

Thanks, Matt

More information about the Linux-audio-user mailing list