Speedstep yay or nay?

[Suspicious-Teach8788]

I have an i7 930 overclocked at 4ghz stable. I was told to turn off speedstep when doing OCs and stuff. I also thought (maybe I was wrong) that when OCed, its not good to have your CPU jumping around, especially because it has to ramp to high voltages, and the spike could cause some issues.

Anyway, apparently I was wrong? I know you want speedstep off when you're benching and establishing your safe OC point, but afterward, is it ok to turn it on? Advisable? If so I feel like an idiot because my system idles at 180W and that's a huge waste of power.

 

[LOL_Wut_Axel]

Yes, it is completely wrong. All that turning off EIST will do is raise your idle power consumption immensely. Ever since Core 2 EIST hasn't affected in any way the max stable overclock you'll be able to get from a CPU, and if your CPU is stable at 4GHz with EIST turned off then it'll be stable at 4GHz with it turned on.

Turn it on.

 

[SickBeast]

OP you should leave speedstep, C1E and all the other power saving features enabled, and you should use offset voltage in the bios to allow the cpu voltage to drop when idle.

To use offset voltage, you tell it how much you want it to add to the stock voltage. For me I used +0.06v and I'm stable at 4.5ghz.

 

[Concillian]

To use offset voltage, you tell it how much you want it to add to the stock voltage. For me I used +0.6v and I'm stable at 4.5ghz.

+0.6v !!

Brave man.

 

[chimaxi83]

I agree with these guys. I can do 5.0GHz @ 1.42V daily and stable on my 2600K with all power saving features enabled, as can most of us.

 

[ehume]

OP - (love the handle, btw) - I have an i7 875k that I OC with stock BCLK. I could go higher, but perversely I find it fun the leave BCLK at 133MHz and let the multiplier run up to 30x on demand. It's fun to hear my PWM fan rev up when the cpu gets loaded.

I leave Speed Step and all the rest enabled. No problem ranging from 1200MHz to 4012MHz. Sure I could tweak it and get a little more performance out of it, but it's fun this way.

So leave your EIST running and all the rest.

 

[Dufus]

First of all when you set EIST enabled/disabled in BIOS it generally means the BIOS enables or disables performance state reporting to the OS, the EIST bit does not actually get reset.

EIST use to be great for power saving in the early days but after the huge improvements made with the higher c-states these far outweigh any savings made by EIST.

I have not used EIST for many years, just let the CPU run at the highest clock to get the work done in the least amount of time then be able to have a longer time in the much higher power saving c-states.

The only time I would consider using EIST is if the higher c-states were disabled.

Also you should actually check what performance states your BIOS passes to the OS. On at least some of the SNB Asus boards the first performance state is 16x then the next step can already be into the turbo multi's.

An older Gigabyte bd BIOS I had using Nehalem was buggy and use to set different values for each thread when EIST was disabled in BIOS. So depending what thread your program run on could end up running sometimes at the LFM other times at the highest set multi.

With SNB you might find keeping offset near zero and using additional turbo VID might prove more stable when using C3/C6. YMMV

 

[bononos]

First of all when you set EIST enabled/disabled in BIOS it generally means the BIOS enables or disables performance state reporting to the OS, the EIST bit does not actually get reset.

EIST use to be great for power saving in the early days but after the huge improvements made with the higher c-states these far outweigh any savings made by EIST.

I have not used EIST for many years, just let the CPU run at the highest clock to get the work done in the least amount of time then be able to have a longer time in the much higher power saving c-states.

The only time I would consider using EIST is if the higher c-states were disabled.

.......

Why disable EIST if it causes no problems?

Most users would benefit from EIST because they spend a fair amount(most?) of time browsing the internet or working on programs which do not max out the cpu.

 

[IntelEnthusiast]

Yea keep Speedstep running as it doesn't hold anything back except when you are doing nothing.

 

[Puppies04]

What everyone else already said.

 

[tweakboy]

If your not a OCer leave speedstep and C1E on.

IF you are a overclocker,, turn both off,,,,,,, and manually OC your system.. gl

 

[Puppies04]

If your not a OCer leave speedstep and C1E on.

IF you are a overclocker,, turn both off,,,,,,, and manually OC your system.. gl

I'm pretty sure you don't have a clue what you are saying, don't listen to this OP it is utter rubbish. The only time you should turn it off is if you are going for insane OCs on LN2.

 

[Rvenger]

My opinion might be different here.

Some motherboards exhibit the idle bug when C1E and Speedstep are both enabled while overclocking (Hardware and software power saving features to throttle clockspeed and voltage) Sometimes with both enabled, the idle voltage will drop too low (i.e lower than 0.80v) which can cause a lock up due to the large increase in voltage and clockspeed that it has to endure when under full load. Somewhere along the lines, the bios isn't talking with the software and it will drop the voltage too low when it is under load causing a BSOD or restart. I hope this made sense.

Keeping EIST enabled and disabling C1E and Cstates would be my personal recommendation to maintain stability. I have worked with various motherboards and some handle these processes better than others.

 

[Suspicious-Teach8788]

I have my vcore at 1.325v for my 4ghz overclock.

With Speedstep on, it seems to hold at the same vcore all the way through too. Is this correct? Or should speedstep also vary the vcore? I noticed that with EIST on, my idle power dropped from 230 down to 200 Watts (original mention of 180 was incorrect).

 

[SickBeast]

+0.6v !!

Brave man.

Yeah I meant to say 0.06v.

 

[n7]

I love using it for my i7-2600k, but i'd say it does make it a bit tougher to go for really high OCs.

If i was purely looking for maximum clocks, i'd likely turn it off.

For a decent OC w/ power saving, i'd say leave it on.

 

[rgallant]

I see most of the power save options great for web beaters.

-but until they give me a time differential I can adjust , I'll stay at max. cpu power.
I allow my gpu's to down clock in 2D ONLY because 3rd party software MSI-AB over rides NV crap down clocking in 3D.
other wise nv drivers down clock my cards during cut scenes or only ramps 1 card back up.

I have no such control software for the cpu. so I leave it at max.
-like they have done great programing for the power save feature's but why is it set for micro sec's. give my a 10-300 minute option before it ramps down and I might use it.

also early x58 bios's had problems ramping up with a high cpu oc's and why people did not use it.
-it also changed per bios release.

 

[Puppies04]

I have my vcore at 1.325v for my 4ghz overclock.

With Speedstep on, it seems to hold at the same vcore all the way through too. Is this correct? Or should speedstep also vary the vcore? I noticed that with EIST on, my idle power dropped from 230 down to 200 Watts (original mention of 180 was incorrect).

If you are saying what I think you are it is because you are overclocking with manual voltage adjustment and not offset mode. Speedstep will let the cpu idle right down to 1.6ghz but the voltage will be pinned at whatever you set it to unless you use offset mode.

Also on a side note, are you using an I5 or I7 because your voltage seems high (my 2500k is stable @ 4ghz with 1.27v and it is by no means a "golden chip).

 

[SickBeast]

You know, one issue I've had with SpeedStep is that in certain games it doesn't clock up and stays at 1600mhz. My FPS go down to the 30s instead of being in the 50s.

 

[Puppies04]

I see most of the power save options great for web beaters.

-but until they give me a time differential I can adjust , I'll stay at max. cpu power.
I allow my gpu's to down clock in 2D ONLY because 3rd party software MSI-AB over rides NV crap down clocking in 3D.
other wise nv drivers down clock my cards during cut scenes or only ramps 1 card back up.

I have no such control software for the cpu. so I leave it at max.
-like they have done great programing for the power save feature's but why is it set for micro sec's. give my a 10-300 minute option before it ramps down and I might use it.

also early x58 bios's had problems ramping up with a high cpu oc's and why people did not use it.
-it also changed per bios release.

I really don't see your problem, under what scenario is the CPU not ramping back up to full speed fast enough? As far as I can see it is almost instant.

 

[Suspicious-Teach8788]

If you are saying what I think you are it is because you are overclocking with manual voltage adjustment and not offset mode. Speedstep will let the cpu idle right down to 1.6ghz but the voltage will be pinned at whatever you set it to unless you use offset mode.

Also on a side note, are you using an I5 or I7 because your voltage seems high (my 2500k is stable @ 4ghz with 1.27v and it is by no means a "golden chip).

Nehalem here not Sandy Bridge. Also while I set 1.32 in bios, CPU-z reports 1.30 only. I do not have an actual reading from a digital meter though.

What is this offset mode you describe? Maybe not in my mobo? (Gigabyte X58A-UD5)

Edit: It seems like this is more of a Sandy Bridge thing?

Edit 2: It seems my board has something called Dynamic vcore.... gonna play around now.

 

[nipplefish]

My specs are in my sig; I've been running a pretty good OC with speedstep on for close to 2 years now without a single stability issue. Pretty much as others have said, you only need to turn that stuff off if you are going for max OC. I have an electric bill to pay, so I'd prefer to not have my CPU running at 4GHz when I'm just surfing the web.

 

[Dufus]

I have an electric bill to pay, so I'd prefer to not have my CPU running at 4GHz when I'm just surfing the web.

But for the most part it is not running at 4GHz if you have C3/C6 enabled. You may find that for more than 90% of the time the clocks are stopped and the cores / package are in a low power state. It only runs 4GHz in short bursts.

DLeRium, you can get an idea of how ineffective EIST is here. The savings for using EIST with C3/C6 vs just C3/C6 are in the order of less than 2W. With EIST disabled the full power of the CPU can be had much quicker. IIRC with W7 default balanced power plan EIST will take some 30ms before transitioning from the lowest performance state to the next highest state. For some people that may mean seeing stutter effects but of course YMMV and in the end it's up to you. IMHO though EIST on todays CPU's is much overrated when it comes to power saving and offers next to no benefit when using the power saving features of higher c-states.

 

[aigomorla]

I'm pretty sure you don't have a clue what you are saying, don't listen to this OP it is utter rubbish. The only time you should turn it off is if you are going for insane OCs on LN2.

wrong...

depends totally on the cpu.

if u have qpi access and bclk acess u turn them off

why? because ur stuck with a stock multiplier unless u have the K chips or a EE chips which then doesnt apply to my statement.

Assumption.

Speedstep lowers multi to the lowest settings and allows the cpu to "idle"

This is fine if ur doing raw multi overclocking... meaning ur keeping the qpi and bclk stock.
Because on speedstep it will go down to 8x while holding the stock bclk which will make the cpu run fine.

HOWEVER the problem happens when your running a high qpi and bclk.

Example.. (not working)
ur running a multi of 10 with a bclk of 200 vs stock 100. In short that gives u 2ghz instead of 1ghz.
When speedstep kicks in it drops just the multi to 8, and still leaves the bclk at 200mhz... which then u go down to 1.6ghz. instead of the factory set 800mhz.
The voltage is dropped to lower then stock values, and if u dont have a nice chip, it will BSOD at 1.6ghz with the voltage speedstep defines, because that idle voltage was locked for 800mhz... and ur trying to run 1600mhz.

Example (working)
Your doing raw multi overclocking... ie K chips.
stock multi is 9x... however u overclocked it to 15x while holding your bclk 100.

so stock speed is 900, while ur overclocked to 1.5ghz.

now speedstep kicks in and drops the multi to 6x. This brings the system to idle at 600mhz.
Doesnt matter if ur at 15x or the stock 9x, when speedstep kicks in its still at the 600mhz hence the speedstep voltage will hold because both will be set at 600mhz on idle.

 

[bononos]

But for the most part it is not running at 4GHz if you have C3/C6 enabled. You may find that for more than 90% of the time the clocks are stopped and the cores / package are in a low power state. It only runs 4GHz in short bursts.

DLeRium, you can get an idea of how ineffective EIST is here. The savings for using EIST with C3/C6 vs just C3/C6 are in the order of less than 2W. With EIST disabled the full power of the CPU can be had much quicker. IIRC with W7 default balanced power plan EIST will take some 30ms before transitioning from the lowest performance state to the next highest state. For some people that may mean seeing stutter effects but of course YMMV and in the end it's up to you. IMHO though EIST on todays CPU's is much overrated when it comes to power saving and offers next to no benefit when using the power saving features of higher c-states.

I just think you are totally wrong here and in your post#7. The link you provided doesn't have any info on the meager savings of 2W.

From what I gather EIST is best turned off because of possible problems encountered during overclocking because of fixed voltages and mb bugs.

EIST can save more power (if the above does not apply) than c-states because my assumption is that users are going to be actually using their pcs a significant portion of the time for lightly loaded apps eg browsing - so EIST can lower freq+voltages and hence reduce power requirements. So the cpu never goes into a halt state for _all_ cores.

Your likely scenario where EIST hardly makes a difference is when a pc only runs jobs that max out the cpu the entire processing time and then goes into a sleep/hibernate stage, and maybe repeat until the pc is switched off.