Talk:HOWTO Undervolt a Pentium M CPU
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[edit] Removing section
I removed the "unsafe" Section because it's damn confusing, and worthless..the values are nearly the same as the safe values...
Yes that's right. This section was a little bit redundant. And there was only 4 CPU with voltage values there.
--Bdz 21:29, 11 February 2006 (GMT)
[edit] User voltage report
I've succesfully applied and used this patch with the kernel 2.6.13.4 (and ArchLinux distribution).
These are my current voltage on an 740 Pentium M:
1100,1100,1100,1100,1100,1100,1100,924,812,700
The system seems to be stable.
151.38.49.234 09:08, 31 October 2005 (GMT)
Thank you for reporting your custom voltages. But can you please confirm that the frequencies of these voltages are the following:
1732,1732,1732,1732,1732,1732,1600,1332,1066,800
Or if your CPU is actually a Pentium M 730 with the following frquencies:
1600,1600,1600,1600,1600,1600,1600,1332,1066,800
Bdz 23:31, 12 January 2006 (GMT)
Yes, I confirm that it is a 740 Pentium M (533 bus) (so 1732 higher freq)
---
Intel provides information about its processors: http://developer.intel.com/design/mobile/pentiumm/documentation.htm Following the links in Datasheets section, you can download pdf files with technical data, incl. Electrical Specifications,but I am not sure how these details should be understood... (I am referring in particular to the table 3-1. Voltage Identification Definition).
[edit] Works with kernel-2.6.16-rc4
The patch "bdz.undervolt.2006.01.07.patch" works with 2.6.16-rc4. Hunks apply with offset.
Pentium M 1.6 GHz "Dothan"
available frequencies
- cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies
- 1600000 1600000 1600000 1600000 1600000 1400000 1200000 1000000 800000 600000
default voltage table
- cat /sys/devices/system/cpu/cpu0/cpufreq/voltage_table
- 1340,1340,1340,1340,1340,1276,1212,1132,1068,988
altered voltage table (stable for me!)
- cat /sys/devices/system/cpu/cpu0/cpufreq/voltage_table
- 1052,1052,1052,1052,1052,988,908,844,764,700
[edit] New Version of the Howto, for version 0.2.1 of the patch
We have released the new version of the patch, version 0.2.1
The project is now hosted on sourceforge Linux PHC
We have changed the howto according to the changes in the interface. We think the new interface is much easier and safer to use.
Please try it and report everything on this page. We would appreciate every kind of feedback.
--Rschwarze 04:16, 2 April 2006 (GMT)
[edit] Stability testing
..should be done with multiple kernel compilations. From my and others' experience, this is much more accurate/demanding than running Prime95, the latter being the method of choice for people who are unable to set up a build environment (or who haven't heard of GNU/Linux). Booting into Windows and using Prime95 really doesn't make any sense if you can already use kernel compilation as a test.
Yes, I can confirm this. I've had no problems with my altered voltage table (C2D/debian sid) until I tried to compile a gentoo package in a chroot (instant crash/reboot). A compile + gcc optimized for your platform is the best test you can get! It's much better as it will test all parts of you cpu...
