Can someone explain speedstep and c-states and how to use them - properly

Soldato
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I know they downclock/reduce voltage when your cpu is under light load/idle - i get that but i want to tune my 3930k so that

At idle it clocks down and lowers voltage

but with any load at all skips to full turbo/voltage

I've been playing BF4 and noticed it keeps clocking down causing cpu spikes which is not what i bought it for....

Is there any combination of c-state/c1e/speedstep i can use to get the above effect???

Many thanks

Dave
 
Soldato
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i think dave want to have the ability to have adaptive voltage and C-states and intel stepspeed to rap down CPU when he is not gaming...which is what 24/7 overclocking should be. i.e. limit the amount of voltage on CPU

I am having the same issue during my photo editing also the CPU spikes...wondering about the same thing.
 
Caporegime
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It shouldn't downclock if under stress

Not sure if coreparking is what's happening in bf4

If your using offset CPU voltage and speedstep and c states are enabled it should work,overclock using CPU multi and leave turbo ratio on auto,it its still downclocking in games try setting all turbo ratio to the same as CPU multi
 
Soldato
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I think the problem with bf4 is it's spreading the load across cores so well they down clock. I've been using dynamic voltage but I might try constant and see if I can't just eek the volts down a bit. On dynamic the chip wants 1.44v for 4.6 which is a little more than I'd like even if it is under water.
 
Soldato
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Im on sandy/ivy so might be slightly different

So heres your 2 options:

Offset Mode: Your CPU will use VERY LITTLE voltage and speed when idling, ANYTIME you idle. (Even browsing can be considered idling.)
Enhanced Halt State (C1E): Enabled
CPU C3 State Support: Disabled
CPU C6 State Support: Disabled
Package C State Support: Disabled

Fixed Mode: Your CPU will run full voltage and speed all the time, even when idling.
Enhanced Halt State (C1E): Enabled
CPU C3 State Support: Enabled
CPU C6 State Support: Enabled
Package C State Support: Auto

I use offset and recently have noticed during some games when the load isnt that high I drop down to my speedstep idle speed of 1600mhz and then back up to 4.8ghz when the load requires it, regardless of my windows power options (Set to high performance, balanced or making a new power profile) so to get the desired effect I would have to run fixed 24/7 4.8ghz. I don't think the dropping of speeds and back to full is actually having any negative effect at least not that I can perceive but would have to try out more demanding games I suppose

You could try something like park control https://bitsum.com/parkcontrol/ to config your desired load states although its exactly the same as what windows power options does I think apart from the core unparking bit.
 
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Soldato
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Thanks Murah, I'm currently running offset mode with c1e enabled c states 3-7 disabled but package c states support enabled and I down clock but the voltage doesn't go down. I will try enabling c-states 3-7 again with high performance profile as I said. I'm on windows 8.1 so I'm not sure I need to until park cores - I think it's handled in a different way
 
Associate
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Speedstep has had cases of this intermittently pretty much since it came out

When you say you've "Noticed CPU spikes" do you mean you've noticed lag in game, or that you've noticed CPU usage jumping?

If you've noticed lag in game then you need to look into it. If you've just noticed that your processor usage percentage jumps up, don't sweat it, it may be that your performance monitor is comparing the current use to the available use INCLUDING speedstep - eg it's taking a percentage of the reduced clock speed.
 
Soldato
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I'm watching the CPU render graph in bf4. Usually it doesn't spike indicating a frame taking ages to render unless you join the game or esc out to options etc but I was getting loads of almost regular CPU spikes
 
Soldato
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i read somewhere C1E might cause some lag...try disable that and enable C3-7 again. Although that didn't help me. I am also running MSI afterburner, so may disable that see it is the gfx card causing my problem

my issue is the usb mouse lag...it intermittently drops and at the same time computer slows down a bit waiting for graphics to catch up.

if i look at the cpu log that's also when the load shots upto 100% from pretty much idling.
 
Soldato
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Well after turning them off then on again, and thinking everything was fine I'm now getting crashes all over the show. I cloned my install onto a Samsung 840pro so it could be dodgy memory and rapid mode, and I've also flashed the bios of my 2nd 290 tri-x... So many things it could be and all I wanna do us play bf4!!
 
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