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Processor Throttling In Windows XP
TomSlick writes "Michael Chu, a former Intel employee, has written up a fairly interesting and readable summary of Windows XP power schemes as they relate to Intel processor throttling. An old topic, but one still relevant as many business notebooks still use XP."
"Many" business notebooks still use XP? How about "virtually all"?
For a second there, I read "Professor Throttling in Windows XP"
Now I know why my laptop burns my legs whenever I use it...it literally IS always on...so that's what my power management was set to. I had no idea that affected the CPU frequency stepping. I guess i just had assumed that was something that scaled intelligently depending on load average or some other *CPU* metric, not a battery setting.
Of course, being WinXP, I should have realized that Foo is actually changed each time I use the GUI to modify the behavior of Bar 1 and Bar 2, which are completely separate system functions.
khasim (12/9/06): In a blind taste test, more people preferred Coke over the Pepsi that I had previously pissed in.
I don't run vista. Could someone try following the paper in vista and explain any differences?
For a while, I thought my fan might have been broken because my laptop was getting very hot. Then I realized that, a few months ago I had messed with the power setting and turned off that technology to make sure I was getting maximum performance out of something. I forgot to turn it back on, and this resulted in the machine running flat-out all the time and getting very hot. Something jogged my memory, I went back to the power settings, and it works fine now. Even DVD playback doesn't force it to run flat-out, so if you have this technology you should definitely use it.
Of course it's only easy to feel the heat with a notebook. If you have a desktop you could be wasting power and not even know it unless you check the settings.
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
and Vista, Mac OS X, Linux, et. al. probably won't change that for at least several more years.
For businesses, the cost of deploying a new OS and the cost of training can be showstoppers no matter what benefits are promised. Imagine the downtime and disruption of upgrading hundreds or thousands of laptops.
At least with Linux, the cost of hardware upgrades required by Vista or Mac OS X isn't in the picture. But several years from now, it won't matter because most laptops in use will have at least 2GB and even business-class laptops will support accelerated 3D.
I bet Windows XP will be widespread on business laptops even 10 years from now. And I'll be using XP software running inside vmware or Wine unless I'm forced to install it as the host OS.
... with AMD Cool'n'Quiet in Windows XP Pro. SP2 even with the latest drivers on my Athlon 64 4600+ (939 dual core) system. It seems like I would get rare random blue screens of deaths (IRQL_NOT_LESS_OR_EQUAL) when playing videos. One time, I had a corrupted SB Audigy 2 ZS driver and I had to reinstall it. I don't have this problem if I don't use the power management (Cool'n'Quiet).
No one was able to figure out why I get them according to this newsgroup thread. Maybe it is because of all my hardware devices I have in this case (Audigy2 ZS, an old ASUS TV tuner, HDTV tuner card, five drives, etc.).
I have not tried to clean install OS (XP installation has been used since 2002 or so), or try Linux. I will try that later on when I have lots of free time. My older Athlon 64 3200+ (754 single core) has no problems in Debian/Linux with powernow-k7 (Kernel 2.6.22-K7), but it is a simple box (only one PCI card for ethernet card [Intel brand].
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
If you run XP, set the power scheme to "Minimal Power Management".
Unless, as a twitch-gamer, you (think you) can't afford to lose even a single CPU cycle, then by all means continue trying to heat your house in "Always On" mode (or the default of "Home/Office Desk", which means the same thing to AC-powered non-laptops).
As an interesting aside, TFA's author recommends "Portable/Laptop" mode; However, he writes that coming from the Intel world. Users of AMD chips (myself included) have noticed problems with CnQ (AMD's version of SpeedStep) not working correctly unless you set it to "Minimal Power Management", which according to the charts in the linked article, should work the same as "Portable/Laptop".
my ubuntu laptop does this intelligently by default. each core runs at about 30-45% clock speed until i launch an intensive application. even in the equivalent mode on XP with the same machine, theres quite a noticeable difference in clock speed reduction and battery life.
I have a Sharp mm20 with a Transmeta Efficeon 1GHZ. It has no fan. I recently replaced the hard disk with a ssd drive and now it has no moving parts at all. It runs kubuntu 7.04. Since it has no fan, the power management is based on CPU throttling.
Some people see CPU throttling as a drawback, 2-3 years ago people complained that mm20 performs poorly because of it. This is stupid. If you want performance you dont buy a 1.9 pound mm20 laptop but a 10 pound monster with a 120W AC adapter.
Transmeta CPUs were great, more powerful than VIA yet they did not need fans. Try find an ultralight fanless laptop these days! A friend has a UX280P Sony UMPC and it has the fan on almost all the time.(sure it runs Aplle MacOSX and Sharp mm20 cannot do that)
http://www.pbus-167.com/
It has a free version and allows you to control the power on all aspects on your notebook, this way you know exactly what its doing. It used to be the first thing I installed on XP laptops, with Vista it's needed a bit less, but still comes in useful as it allows you to switch profiles with much more ease than the normal Vista speed control.
My first guess would be an overloaded power supply. Second guess would be crappy audio (more likely) or video (less likely) drivers.
You should give a clean install and/or a bios upgrade a shot. It wasn't even needed here though.. Turned it on in the bios, installed all AMD drivers and turned on the power management to minimal power. Now the cpu (Athlon 64 x2, 4400) is running at 1000 Mhz most of the time. It's lovely.
:)
No problems with my old hauppauge Nova DBV card either. I doubt that C&Q is your problem. Set up a clean system and enjoy the benefits..
I already have thelatest BIOS from http://global.msi.com.tw/index.php?func=downloaddetail&type=bios&maincat_no=1&prod_no=249 ...
:(
I will try clean install when I have time. Reinstalling and reconfiguring hundred of software and games is a pain!
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
Isn't 600 watts SeaSonic S12 PSU enough? I don't use cheap PSU brands either. Yeah, NVIDIA and Creative have crappy drivers. What can I do? NVIDIA = newer games require newer drivers. Creative hasn't updated its drivers. I refuse to use onboard sound and other sound cards because of lack of EAX support in games. :(
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
Laptop heat a threat to fertility
http://www.news.com/Study-Laptop-heat-a-threat-to-fertility/2100-1044_3-5485763.html
I wouldn't hazard a guess as to whether this problem actually applies to very many people who read Slashdot, though.
After using WinXP, it's not the processor that wants to throttle the system - it's me. So I installed Linux instead.
Take Nobody's Word For It.
"An old topic, but one still relevant as 99% of business notebooks still use XP."
Seriously, why do you think all laptop makers have instructions to downgrade to XP. And, Microsoft knows they got a lemon because the Vista license is also good to use if you downgrade to XP. I recently did this with three Thinkpad T61's.
as a cpu throttler.
boycott slashdot February 10th - 17th check out: altSlashdot.org
Sure, just pick the "Windows Classic" Theme. It'll be much like you remember graphically. Start button reading "Start" and everything, all in gray.
That said, I don't know WHY you'd want to - I've never really understood the appeal of atavistic GUI except for those with really old GPUs. But it's in there.
Perceptually, I'd say using "Windows Classic" seems more clunky and perceptually slower, part of that because it looks slow, and probably in part because it means my CPU is busy doing work that my GPU should be doing instead.
Myself, working in video where color perception is critical, I just customized the default Vista appearance by turning the background color and window shading to R'G'B'=127. I get the performance (no trails!) of Aero Glass, the nice Segoe font, transparency, etcetera, but in a way that doesn't mess with my color perception.
Really, Vista is as themeable as XP was.
My video compression blog
Its not just business laptops that are using XP. The vast majority of people still use XP. Heck, even amongst average gamers (where you'd expect ppl to upgrade to vista for DX10 games), less than 2.5% have vista and a dx10 capable card.
Apparently so.. http://www.pendrivelinux.com/
It is difficult to get a man to understand something when his job depends on not understanding it.
It seems there are some problems with cool'n' quiet and some hardware. My Nebula TV tuner card was getting random glitches when watching live TV or recording. I have a 939 Athlon single core and an Asus A8V board in my PVR, and it worked fine when I turned that feature off in the bios. Try removing the TV card and seeing if the problem persists.
On my Linux box, it seems to work fine. The boot up for Fedora 6 complained quite a bit when I didn't have it enabled, and it throttles the CPU speed quite nicely too. I'm running at 21-25degrees C with the stock cooler while idling, and going up to about 35-40 under load. Could be the AM2 CPU or perhaps it is more compatible with the hardware in the Linux box.
It is difficult to get a man to understand something when his job depends on not understanding it.
"CPU(s) begin in lowest performance state and then get slower and slower"
This is remarkably sloppy writing for a supposedly technical article. Is there a performance state even lower than the lowest? Is he talking about clock modulation? Does it get "slower and slower" but never faster and faster?
XP can throttle your CPU, but Vista downright chokes it.
You are in a maze of twisty little passages, all alike.
Vista is a failure. Instead of spending your money on the next generation lockdown, demand your software freedom. Send your laptop back if power management does not work under Ubuntu. Make vendors pay for their misplaced loyalty to Microsoft and big media companies. Make them serve you instead of them.
Try to uninstall the dual core optimizer. In my system (X2 4800+), the random kernel deadlocks (or livelocks) with the Flash plugin and the Opera web browser have not occurred since. Also, I am not sure whether the dual core hotfix (kb896256) has an affect on stability with the power management modes activated. See also system voltages and check other BIOS settings, especially make sure you have the correct settings for the memory array.
CPU throttling is the topic and the post is about this.
...if you don't , like I don't (Dell E1505) where manufacturer screwed up BIOS so 2nd column is always CPU(s) run in highest performance state.
ACPI is still not sabotaged, and it won't start being sabotaged just because you wish it was.
One day you'll realise that all you have as 'proof' is an email that is not only nearly nine years old but completely at odds to the fully working ACPI implementations on OS X, Windows and Linux. ACPI is an open spec. To sabotage it would be to have every part of that sabotage documented for people to read.
I suggest you go read it and quote the specific parts of it that are Microsoft-only, then copy them up here for everyone else to look at.
"It does not do to leave a live dragon out of your calculations, if you live near him." - Tolkien
You need to have a conversation with those who try to make ACPI work to spec in Linux then. Its an open spec, Linux is open source, now ask them why power management doesn't work as advertised. It was discussed heavily at the OLS two years ago as I recall. There's PDFs on the site if you want to read the presentations.
- Michael T. Babcock (Yes, I blog)
Speedswitch allows you to switch between battery optimized, max performance, max battery, and dynamic much like the Intel applet. Speedswitch is also able to configure a bunch of other power features.
You want fun, go home and buy a monkey!
First of all, if you want interesting information:
/proc/cpuinfo
cat
The speed listed there is, in fact, your currently running speed.
But more relevantly: I've installed Ubuntu Feisty on three machines now which had CPU scaling -- two separate AMD desktops (one dual-core, one single-core) and one Intel laptop (dual-core). On all of them, CPU scaling was automatically detected and enabled, in a reasonably intelligent manner -- most of the time they all run at 1 ghz, but they can and will crank up to 1.8, 2.0, or 2.4 (depending on the machine) when needed.
I would say that there's really not much reason for manually changing the profiles, either, unless you need to force them to be slower. I think it can be done, I've just never cared to try -- if I don't want it to heat my lap, I don't run CPU-intensive stuff.
One thing Windows likely can't do: Laptop Mode. You may need to Google for help here, and you'll probably want to manually force your hard drive to be able to spin down, but what this means is, you can essentially force your computer to keep the hard drive off as much as possible, delaying reads as long as everything's cached, and delaying writes until the buffer is full. Then, when forced to spin up, it flushes all the writes to ensure that by the time it spins down again, it will last just as long.
Don't thank God, thank a doctor!
I tried to get PDFs from that site but ended up going around in circles, and it's not abundantly clear from the page you linked me to where to get them from, other than by "calling".
"It does not do to leave a live dragon out of your calculations, if you live near him." - Tolkien
You might be happy to know that EAX is being phased out. Most all new games from the last four or so years support OpenAL audio which has a component called EFX that is replacing EAX for the most part-- and it works with ALL modern sound cards, not just those from Creative Labs.
I saw a box sold with Home Basic which had something like an 80 gig drive, 512 megs of RAM, and a 1.7 ghz processor.
It was absolutely unusable.
The processor was not a bottleneck, I'll give you that much. And I didn't stay on it long enough to test if the network was the bottleneck -- that whole sound-drops-you-to-10% bug (a fucking BUG, not a feature) -- but I can pretty much guarantee it wasn't, for this simple reason:
The RAM killed it. Even if it weren't for the network bug, it'd still browse slower than dialup, because it was CONSTANTLY swapping out.
No, not "Often", or even "Most of the time". Not only when I, as a geek, was trying to coerce it to do more than it was designed to, like, say, download some updates, or install Firefox.
It was swapping ALL the fucking time. I popped in a 512 meg USB stick and used it for ReadyBoost, which improved things marginally -- it was then capable of doing some things in maybe 20-30 seconds, instead of 2-3 minutes. And by "some things", I mean opening another tab in a browser -- Firefox or IE7, didn't matter. (And like 5 minutes or so to switch between them...)
I may be getting the times wrong, but let me put it this way: I've used an NT4 machine with some 128 megs of RAM. I've used a Win98 machine with 32 megs of RAM -- also a Linux handheld with 32 megs of RAM, and that had to use a CompactFlash card for swap.
That 512 meg Vista machine was the absolute WORST computing experience I've ever had. Ever, in fifteen years. The only thing that comes close was a videogame on Win3.1, running off a 4x CD-ROM drive, but at least it was fast once it loaded the damned level.
So yes, I realize Vista can be fast. But considering that it sucks so badly, even compared to older versions of Windows, on 512 megs of RAM, you have to ask yourself, are you actually getting to use the rest of your RAM? Say you need to run a memory hog app like Eclipse -- Vista could be the difference between needing 2 gigs of RAM for Eclipse and nothing else, or needing 1 gig of RAM and being able to play music and still have a fast network.
Didn't even touch on disk usage, but there's really no excuse there. After installing Kubuntu, plus a bunch of codecs, plus a bunch of apps not in the main install, including a couple of versions of Wine and some Windows apps, it was maybe 5 or 6 gigs. The above Vista install was 15 gigs, before you go download drivers, VLC, install Office, etc. Consider that there was also a restore partition, not even a hidden one (it was mounted), which used maybe 20-30 gigs (and wasn't even entirely full), and it's an 80 gig hard drive, total. Which means you're giving about half your hard drive up to the fucking OS, before you even install software. Sure, it's inconsequential for your 300 gig drive, but it is a waste, don't you think?
The question is not whether there's hardware that can run Vista well. That's a given. The question is whether you'd be better off with XP, and more and more, the answer is a resounding yes!
Don't thank God, thank a doctor!
Interesting. I wasn't aware of that. That's good news for me!
Um, is there an OpenAL hardware sound card? Do all newer motherboard's onboard have this hardware based now with no CPU usage?
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
I was quite dissapointed with SpeedStep, especially on dual/quad core processors. The lowest possible multiplier is 6x, which works out at about 1.6GHz, still very high for idling on four or even two cores. I don't see any reason why it couldn't drop a lot lower, if not by default then at least as an option.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
RMclock (a small free utility) allows you to
1) Specify more accurate power schemes
2) Reprogram the voltage and throttling in most Centrino platforms
3) Unlock power-related settings in your platform to achieve even higher power savings
All these result in better silence and longer battery life.
In soviet Russia, the Processor throttles YOU!
Prov 9:8 Do not rebuke mockers or they will hate you; rebuke the wise and they will love you.
Actually, Intel's power-saving by throttling the CPU load back is an ugly hack. I don't think that it's completely worthless, but it's still an ugly hack. Motorola's Power PC chips originally pursued a design of low power usage, but as the PPC business alliance disintegrated, and IBM kept pushing the performance envelope for server applications, the PPC architecture just got more and more power hungry. The final Mac generation, the G5, made an awesome workstation platform, but Apple could not shoehorn it into a portable.
The correct approach to power-utilization problems is to push for chip efficiency. Running full-on top-speed at all times is pretty dumb - but intel isn't pushing efficiency either - they're throttling back to save energy. Now; if I have to do X amount of work, and I have Y time to do that work, and if I'm on battery, you slow my CPU down, I'm not going to get that work done any faster. . . either the battery is going to do the job for me or not. Slowing my machine down does not solve this problem. Giving me a CPU that does more with less power (Transmeta!) solves my problem.
Given that Motorola and Transmeta tried to solve this problem (and gave up) - I can't really credit them much more than Intel. I hate their approach, but at least they did *something*.
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
The GP claimed Microsoft had sabotaged ACPI -- I simply was pointing out that ACPI is in fact broken, and not functional as per the specification as it seemed you believed.
The presentation PDFs are available in big chunks (you'll have to search) from the proceedings page.
- Michael T. Babcock (Yes, I blog)