Matching new motherboard, kernel, and BIOS settings

[depontius]

I have a new system installed and running Gentoo, and have been tweaking as I go. But I'd like to tweak (or shall I say "rice"?) it a little further, and have some questions about matching the new motherboard, kernel, and BIOS settings.

The motherboard is an "ASUS M4A785TD-M EVO." (I think it's an AMD 785G chipset.)
The processor is an "AMD Athlon(tm) II X2 255 Processor" stepping C2.
(Strings courtesy "dmidecode", stepping from BIOS.)

1 - I see settings in kernel config about "ACPI-4.0" features, and so far have not turned them on. On the web I see that the ACPI-4.0 spec was out in mid-2009, and my BIOS is dated mid-2010. So it's quite conceivable that I have ACPI-4.0, but nowhere can I find anything definitive to that effect, neither in BIOS settings nor in dmidecode output. How can I know, or should I just try building the stuff as modules and see if they load?

2 - The "C1E" power mode is disabled in BIOS. A little time on google suggests that I can enable this to lower my power, but there are mixed opinions as to whether it's properly functional at the C2 or C3 stepping. (I have the former.)

3 - I have "Cool'n'quiet" turned on in BIOS. Do I need to enable anything in the kernel or install any userspace software to go with this? Am I just running on the grace that I haven't taxed this system, and it's waiting to burn up the first time I run it hard?

4 - There's another item, "Advanced Clock Calibration" that is currently "Disabled". It can also be set to "Auto", "All Cores", and "Per Core". A quick search and I see that it's primary use seems to be overclocking, which I don't do. Are there other reasons, perhaps further power saving by underclocking, for me to enable it? (I'd think "Per Core", myself.)

I thought powertop might tell me a little more, but at the moment the only thing I can see is that when I press "U" to enable USB power saving, my USB mouse goes away.

Thanks for any info,
Dale
_________________
.sigs waste space and bandwidth

[roarinelk]

1- you can enable it, but no consumer hardware supports acpi 4 features, let alone acpi 3
(blame windows, it only supports parts of acpi 2). it's safe to have it enabled at all times.

2- disable C1E; it causes massive headaches (systems pausing for no apparent reason until
a key is pressed, ...). The power savings gained from it are negligible.

3- enable CPU frequency scaling, the ACPI cpufreq driver and a governor ("ondemand" is a
good default choice). You can't burn the cpu anyway: they have thermal circuitry which
cuts power when a critical threshold is reached.

4- no


and the ATI/AMD USB controllers suck at life.