Snakeoil Forums

I would welcome anyone's input about BIOS settings that might improve SQ. Meanwhile, I'm trying some myself and have a question or two relating to under-clocking the CPU; i7-7700T in my case.

With Intel Speed Step (EIST) enabled, my BIOS shows the CPU running at 800MHz. I know that under load it could step up to 2.9GHz (and if I enabled Turbo, it could go further to 3.6GHz). I'd like to find out what frequency it is actually using when Snakeoil is running and music playing. In "Dashboard" on the web interface, Snakeoil shows it as still running at 800MHz and this remains the same, even when I refresh the page while playing hi res files. So my first question is whether that Dashboard frequency reading is live (at least when I refresh page) or is it not really a reflection of the CPU frequency in use at the time?

Cheers,
JD

Hmm. Don't really know. What you can do is try and run the cyclictest on one page, and then load another browser tab and look at the dashboard again. Does it turn up? Playing music doesn't require a lot of CPU at all - as such it may not 'ramp up'.

(23-Dec-2017, 12:00 PM)agent_kith Wrote: [ -> ]Hmm. Don't really know. What you can do is try and run the cyclictest on one page, and then load another browser tab and look at the dashboard again. Does it turn up? Playing music doesn't require a lot of CPU at all - as such it may not 'ramp up'.

Tried that; freq on dashboard never changes so I think it must be static.

You touched on another question: Might cyclictest be CPU-intensive enough to switch on turbo or otherwise ramp up CPU freq?  If so, the results may not be relevant to the lower CPU speed when actually listening to music.

BTW; it was not speedstep that slows my CPU to 0.8GHz. Just disabling turbo does that regardless of other settings.

I worked out the following:
With Turbo set to Auto BIOS shows CPU running at turbo frequency of 3.6 GHz (live) but after Snakeoil is started, all tests show it at "normal CPU freq of 2.9GHz
With Turbo disabled (regardless of settings for Speedstep, Speedswitch, C-states) both BIOS and Snakeoil show 0.8GHz and it definitely doesn't increase from there even under very heavy load.

Tried monitoring CPU freq with commands like;
nano /proc/cpuinfo
watch -n1 "cat /proc/cpuinfo | grep \"^[c]pu MHz\""
...not sure they are live but they match dashboard and I am confident the reading of 0.8GHz (no Turbo) are correct because upsampling in Roon to 2xDSD took CPU usage to 100% compared to 30% with Turbo enabled; where they all showed 2.9GHz

So strange that I can't achieve the CPU specs of 2.9GHz unless Turbo is enabled and strange that Turbo does is real job (3.6GHz) in BIOS, which should be low load, but not in Snakeoil under high load.

Wow, you're quickly turning in a Linux guru. Well done doc!

Could be the kernel too.. Not all CPU power saving features are installed.. Will look into this more in the new year.