Hello. I know sufficient about c2d overclocking to make stuff stable and working. But I've always turned off c1e and speedstep in order to get there.
But what if I want speedstep enabled?
I read somewhere that the ordinary haltstate only cuts the fsb from the circuit and thus only marginally lowers power consumption. So I was hoping on speedstep to do the trick. But I've asked on a local board, and they tell me that if I change the cpu voltage from auto speedstep'll not touch voltage, and if I leave it on auto and oc the bios will raise the voltage and again turn off speedstep.
So. Can I do it somehow?
My plan is to oc an e6600 to 333x9 on stock cooling and pray that it won't crash when speedstep kicks in and lowers the cpu to 2ghz - but if it only lowers the multiplier it won't really affect power consumption in any notable way...
Edit: specs:
e6600 with stock cooling
antec sonata 3 with 500w atx 2.2 psu
ga-p35c motherboard (the one with ddr2 and ddr3 slots)
8600gt
2gb corsair pc2-6400cl5
2x250gb sata in raid 0
Quite often with speedstep,as with AMDs coolnquiet,leaving it enabled when overclocking causes system instability.I don't remember exactly why it does this,but it has to do with original clock speeds of the identified processor.At any rate,it's been my experience that with overclocking,bothe need to be disabled .Otherwise the system when it goes to clock down,becomes unstable and hence your computer crashes or freezes.Goodluck.P.S.It does effect power consumption by lowering the voltage to the cpu,thereby reducing power needs,thereby reducing power consumption.
Dahak
AMD X2 5600+ @ 2.8ghz(stock)
M2N32-SLI DELUXE MB
2 GIGS DDR2 800 RAM
THERMALTAKE 850WATT PSU
7950GT KO(WAITING FOR MY OTHER TO COME BACK FROM RMA)
ACER 22IN. LCD
SMILIDON RAIDMAX GAMING CASE
80GIG/250gig SATA2 HD's
XP MCE
Speedstep *IS* Achievable while overclocking depending on how far your pushing it. Speedstep works by dropping the core multiplier and the voltage... so if you have your FSB too high, when that core voltage drops due to speedstep it will cause a system crash. So really, the only way to find out with your current settings if your system will run stable with speedstep is to overclock to a stable level, turn speedstep on and see if it can stay stable in its energy conserving state. There are several C2D overclocking guides that explain this in more detail as I am... only a noobie regurgitating what I've previously read.
dahak - I know a fair bit about it already. The amd stuff doesn't work, because the windows driver amd made doesn't account for overclocking.
With intel though, you don't install a driver to do it, windows just 'magically' does.
@ both - I know it can run while turned on. What I've heard though, is that it will only lower the multiplier, making the system run slower but not lower the voltage of the cpu - thus consuming almost the full wattage at 2/3 the speed, making it useless.
What I'm actually asking is :
1) Is it true that overclocking the fsb will make speedstep not touch the vcore setting? but only multiplier?
2) And do I enable only speedstep or also c1e? c1e makes the core skip some fsb clocks, thus potentially lowering clockspeed by some amount I don't know. Presumably lowering fsb from 266 to 200 under stock conditions or something along those lines. Will that work with fsb oc'ed? if so, it'll greatly increase chances of the cpu handling the effective low-power state without crashing (since it may reduce the cpu to 266*6 @ 1.1v or so)
Does anyone have a concrete yes or no answer, or a guide which does?
Speedstep or rather EIST as labeled on new MB, will only affect CPU multiplier, not the actual FSB clock, thus lowering the CPU speed. It won't affect the vcore. Just test by yourself to see...
C1E, will lower the vcore on idle state.
Enabling both is needed for optimal power management
On the P5B Deluxe: enabling both at my high vcore: C1E no longer triggers. So, at high vcore, most MB (AMI Bios) will disable C1E. Check for your setup to see if it's the case (don't use CPU-z to monitor vcore)
In my case, enabling both, even that only my CPU frequency is clocked down (multiplier from 9 to 6), my system is unstable on long use (random crashes)
So, as said before: overclock with C1E/EIST disabled. Enable them when you reached your liked stable overclock. On daily long term use, if you have crashes, disable them, if not, you're lucky and should keep them to be "green eco label"
I can't possibly see why it should become unstable when it clocks down to 6 multiplier, if it doesn't touch the vcore ... it's not like it's stressing the cpu more after all.
Anyhow, if the gigabyte and the asus are anythign alike I suppose it'll also leave the voltage alone on the gigabyte one ... as I feared.
As for trying - now that's the hard part. I've got approx 8 days to build and set up the system - and I haven't even ordered most parts yet.... and after those 8 days I hopefully won't be seeing the system again. That's why I wanted to collect some knowledge beforehand, given the lack of experimenting time.
What?? cool & quiet bugs in windows ?? On all my athlon64 I never had problems leaving it activated and overclock to the max of the machine.... Don't say it bugs if you didn't tried it.
What I've heard though, is that it will only lower the multiplier, making the system run slower but not lower the voltage of the cpu - thus consuming almost the full wattage at 2/3 the speed, making it useless.
Your right it will only modify the multiplier but it is far from being useless if it lowers your temps when idle. That is what someone leaving it enabled is thinking: saving some heat when idle and lotta power when needed.
My old athlon 3500+ worked with the cool'n'quiet so long as I kept it within 10% of specs, but beyond that it would bluescreen when the amd driver loads - because the driver is not considering the possibility of a vcore change.
With the opteron I had after that one you couldn't even oc 1% before it crashed on cool'n'quiet - and ever since I've made sure to not activate it.
So I HAVE tried it, and I HAVE failed making it work. I even tried 3 versions of the driver - even though the newest was hopelessly old.
I don't hate amd or anything, but cool'n'quiet does not work when overclocking.
Edit: and idle temps shouldn't be reduced by anything more than 1-2% if you're only changing multiplier ....
vcore makes the signal strength more stable - and produces more heat - multiplier clocks the cpu - higher vcore is needed to increase the fading signal strength when oc'ing the cpu. It's the vcore supplied that generates heat, not the actual speed.
Also the northbridge heats equally much if it's running 333 or 266 - as long as you don't change mch voltage.
In english : vcore and cpu state determines heat production, not cpu speed
That's not totally true
vcore is the main responsible for heat production, but at same vcore a 3.2GHz C2D will generate much more heat than a a 1.8Ghz one
You can also try that yourself, lowering the speed, while keeping vcore high
Speed -- > heat. Heat is energy, energy is power. So yes, you will definately consume more power on high cpu clocks for same vcore. Now, to see the real gain, you will need an external wallet mesuring device to check power drawn from your PSU. Tom's guides recently edited a nice article where they measured a 15W decrease at stock speed with the C2D extreme when enabling ESIT/C1E. They sadely didn't test ESIT alone
Someone with the right material, should enlight us, but the gain should be marginal: less than 50% of 15W: 7.5W at the best of the best
For my setup and overclock (see my sig), my CPU power consumption is estimated at 180W. Only lowering my speed with EIST (6*346=2076Mhz), if their estimation is true, I can reduce power by 60W (120W consumption)
Of course Tom's guide was made at default speed, and we all know overclock needs too much power, especially some high 72% overclocks or above like mine
I also tested the Tom's guide setup: X6800, with ESIT/C1E enabled: the calculator shows a 20W decrease at 1600MHz (6*266)
So, yes, the calculator looks to correspond to real testing, so maybe on high overclocks, the gain can be significant.
I'll try to enable again ESIT alone and check stability, If I can gain 50W, than why not :-)
but can someone explain how one can save 20W or more by simply clocking down the system at idle?
If the system in general ran 1.8 instead of 3.2 I'd understand why it generates less heat - because the various circuits are more likely to be used when more operations are used in the same timespan (at higher clock) .... but at idle it wouldn't be using any circuits more often, cause it'd just execute the few commands it has to and won't exactly have a huge queue of commands needing to be executed - that could alter the heat output with a higher clock .... that's my understanding of it anyway.
Can someone explain how I'm wrong? and it's entirely possible that I am....
I think you're partially true: the largest gain should be on load of course. But even at idle, it should be some gain: the idle temperature is the reflect of power use: at same vcore, heat increases at idle with speed, so do power use (it is the power used that generates the heat). There is a nice thread here showing the relation between temperature/FSB/vcore
By the way, I tested the Speedstep technology alone without C1E on my current overclock, so far stable, with temperatures at idle lower by about 3-5°C
okay ... a 3-5C decrease in temp should be an indication to speedstep indeed doing something .... unless the ambient temp was 3C lower than normal ....
