Bitcoin Forum

Lower your CPU's core speed :)

ATI's CCC has a CPU Power section under Power, that will allow you to change the CPU core speed on the fly...dropped mine from 100% to 50% and it saved me 40W from the wall (and dropped CPU temps by about 8c, stupid 100% CPU core bug still) on my AMD Phenom II X6 1090T.  Similar changes can be made in the BIOS as well.

For dedicated mining rigs, you really don't need your 100% as mining is not using the CPU for much, if anything.  Save some power and shave some costs off your electricity bill.

true, tho my 1090Ts are running 100% mining litecoins ;)

Then by all means, overclock that beast !

I don't know why I didn't think about downgrading the clock months ago, but oh well...time to reap in the "profits" from it meow :P

you could probably under volt it too. shave a few more watts off.

my tip for maximal cpu profit is mine solidcoins with your cpu :)

Anyone have  a command to lower the cpu speed? I would like to lower the click speed via ssh. I'm on ubuntu 11.10.

http://bit.ly/vEJofy

Being an AMD product, can CCC do this on Intel CPU's too? I just do it in the BIOS, but it would be nice to do it "on the fly".

I was curious about this also, but haven't had the desire to go look.  No Intel-CPU's allowed in my dwelling.

So this 100% CPU bug everyone is talking about.  Its just an issue with Linux i'm assuming since its easy to limit the cores for an application in Windows.

I see a lot of people still talking about it and just wanted to make sure everyone knew.

-pirate

You think it's hard to specify cores on linux ?

What if I have only one core ?   Like a 3.4ghz Pentium 4 consuming ~120watts ?

I know nothing Linux.  So I just wanted to make sure.  Adjusting the priority does nothing either?

Adjusting priority ?  If nothing else run this will run 100%,

Anyway limiting to a single thread is a very partial solution, 50% on dual cores.

Ah, I see.  I have not been on any machines to test with a single core.  So what about setting up a user account with a cpu quota set in the registry to 50% (which i think is the lowest). Just thinking outside the box here if the AMD tool doesn't work for Intel chips.

 

Lol! Do you fear high performance? J/k

Which version? I was just checking, I have 11.8, and after looking around a bit, I don't see anything for any CPU clocking. So, it must be a newer feature!?!
I would imagine it would be an AMD overdrive type of thing, which is likely only going to work on AMD CPU's.

Doesn't matter! Windoze has it too!

If the machine is a standalone miner you can set the max cpu usage in the power options in windows.  I was thinking for people wanting to use their computer while mining.

Bad assumption. I'm down to one dual boot machine with Windows XP Pro, the 100% bug is not present with the ATI video driver 11.6, but is in later releases I tested; I think the current one is still 11.11. Windows has been obsolete here for several years, so I've never messed with the 64 bit versions.

OTOH, Either 11.6 or 11.11 work *without* the 100% bug on 64 bit linux, however, versions in between, e.g. 11.8, manifested the bug. We retired the last 32 bit linux box about a year ago, so no experience there either.

Also, it's trivial to set processor affinity in linux, see schedtool. This works well in scripts, which work well in systems that are not tended by computer-directed mouse actuators  :)

There is a program called "Speedswitch XP". A long time ago before I ever mined I had installed it on an old Compaq. That compaq has a single PCIe so I run a mining card there as well as the bitcoin client; I always run this miner even if I shut down other rigs. Using Speedswitch XP in "battery maximized" saved me about 20w according to my Kill-a-watt. (battery maximized downclocks it to about 900 MHz; it's an Athlon 64).

Unfortunately Speedswitch XP does not work on newer processors, it is rather old. To save some watts on my main rig that runs 3 cards (Intel Core 2 Duo with motherboard that has 3 full PCIe slot), I disable one core in the BIOS, and downclock the speed. That whole rig only uses about 550-580w and it runs, 2x Radeon 5770 and a Radeon 5850.

Can not figure out how to disable cores on a Mac Pro though. It is my main workstation but sometimes it mines in XP with a Radeon 5770  but wastes some watts running extra Xeon core.

CCC doesn't supprt Intel CPUs.My mobo is an Asus model so I can use EPU-6 utility to really reduce my CPU volts and clock speed.It's like a BIOs tweak but within windows :-)

For convenience set it to Auto.I put mine on Medium power savings (as Max power saving switches off my case fans on my PC which are needed to help cool my system down)

Takes some tweaking but it's worth it.I shaved off 35W by using that tool plus a further 10W by enabling Green Ethernet on my NIC (cable is 20m long so energy use adds up) plus 5W from disabling firewire,saved 8W by switching to SSD from system HDD and 13W by removing 2 HDDs and replacing them with 1 2TB eco HDD which uses only 3 watts (instead of using 16W from 80GB and 750GB HDDs like before)

So total energy saved is:71W from all those mods.

Pretty damn impressive for power savings huh.

My CPU is a Core i7 920
6GB RAM (CPU and RAM underclock together to save even more power)

But that then begs the question of why are you paying for an i7 920 if you are going to cripple it so much?

Ensign-lee,that is a good question.When I first purchased the Core i7 920 CPU,my needs were different as they were very CPU intensive like film editing certainly was as I was working on large projects and every second counted.That was back in 2009.Fast forward 2 yrs later,my needs have changed to GPGPU use thanks to optimisations in the apps I rely on for film making and editing so the CPU doesn't get used much these days.The CPU is only used (and therefore put in Turbo) when an important app I need isn't GPGPU optimised (due to laziness of the developer not using OpenCL and only using CUDA as I have a radeon)

Funny you saying that,it isn't the CPU that's cripped so much but I can understand why you would think that.A little known fact is that the X58 chipset on socket 1366 mobos (esp mine) can use up to 30W just for the chipset whereas from westmere gen and beyond (mines a nehalem) uses just around 6W which is quite a saving,then of course swapping out HDDs for 1 large one and an SSD plus disabling unneeded ports on my mobo saved the rest.The CPU was only modified a little (lowered 1.6GHZ speedstep down to 1.35GHZ which saved me a lot of power),My mobo has a lot of 'eco' settings onboard so the rest was childsplay for energy savings. :-)