How cpu throttling killed my fps and how I fixed it.

[clockmasher]

I bought an Intel I5 760/Asrock P55 deluxe3/G460 rig last August and have always thought that the cpu was running at an overclocked speed of 3.8 ghz. I was careful to turn off speedstep and C1E, both Intel's speed control technologies, to make sure the cpu was only running at 3.8 ghz. Indeed programs such as cpuz verified that my cpu speed was at 3.8 ghz. Since this rig was a substantial upgrade over my ancient 5 years old AMD machine, my perception of wow performance with this then new setup was that it was adequate. I reconcile my inability to have smooth gameplay at ultra setting (at least 60 fps) to not having top of the line gear (I7, G480+. etc...).

Yesterday, I noticed my windows 7 gadget that displays cpu info, All CPU Meter, was showing the frequency at 4.0 ghz. This directly contradicted info from cpuz. I then went looking for a better gadget that would produce the correct frequency. I installed Core Temp, and discovered something totally unexpected. My CPU frequency was fluctuating constantly. Most of the time it stayed around 1.5 ghz. Only when I ran a cpu-intensive program, like Prime 95, would the frequency max out at 3.8 ghz. The program was showing me that the multiplier part of the equation (CPU frequency = BCLK(base frequency) X multiplier) was constantly changing, probably due to workload. I immediately thought that Core Temp was broken, and went looking for other frequency programs. While ASROCK OC Tuner showed 3.8 ghz, RealTemp showed fluctuating frequencies like Core Temp.

I then fired up WOW to see what these two programs, Core Temp and RealTemp, showed during gameplay. To my utter surprise, at no time during tested gameplays(all except raid), did my frequency gone past 2.5 ghz.; cpu utilization never reached 100%. I began to strongly suspect that I had been running under-clocked all this time.

I dug a little deeper and found this little entry in the bios called c state tech, a setting that controls cpu energy conservation. Upon turning it off, both Core Temp and RealTemp reported solid unchanging 3.8 ghz. When I re-entered WOW, I was shocked. The difference was startling. I can now run around Origrimmar at 60+ fps at 1920/ultra. I ran a five man and fps never dipped below 60. There is a noticeable difference between gaming at 3.8 ghz vs gaming at 1.5-2.5 ghz.

I highly suggest those out there who overclock their machines and expect the absolute best fps, energy conservation be damned, to find out exactly what frequency your rig is using.

So what are the important takeaways?
1. If you want top overclocked performance, turn off speedstep, C1E and c state tech.
2. Sometimes trusted program like CPUZ lies.
3. Use Core Temp and RealTemp to find out your cpu's exact frequency in windows.

[Shaqur]

In first place, why haven't you visit overclock.net?
They are professionals with overclocking believe me. I could easily reach 4GHz on dual core processor with little of their help ;p.
Anyways you got nice clock. Make sure you don't overvoltage your cpu and keep watching for temps. Cleaning case is very important so is PSU-Power Supply Utility. Make sure its quality ;p

[Quenios]

In first place, why haven't you visit overclock.net?
They are professionals with overclocking believe me. I could easily reach 4GHz on dual core processor with little of their help ;p.
Anyways you got nice clock. Make sure you don't overvoltage your cpu and keep watching for temps. Cleaning case is very important so is PSU-Power Supply Utility. Make sure its quality ;p

wtf did that have to do with anything he just posted.

OT: Nice post, I don't believe my Asus motherboard has such a feature. It might just be AsRock?

[Falkus]

wtf did that have to do with anything he just posted.

Perfect example of how people don't read the entire post or fail to comprehend what was just written.

OT: Nice post, I don't believe my Asus motherboard has such a feature. It might just be AsRock?

Newer Asus motherboards may have it. Or similar stuff to it, at least.

[bryanmathis]

for older amd boards/cpus the "Cool n' Quiet" option sometimes does the same thing. if anyone was wondering =P

[Narshe]

In first place, why haven't you visit overclock.net?
They are professionals with overclocking believe me. I could easily reach 4GHz on dual core processor with little of their help ;p.
Anyways you got nice clock. Make sure you don't overvoltage your cpu and keep watching for temps. Cleaning case is very important so is PSU-Power Supply Utility. Make sure its quality ;p

Perfect example of how people don't read the entire post or fail to comprehend what was just written

The OP was talking about BIOS settings, nothing to do with PSU or voltage settings. Shaqur is the one who didnt bother to read what the OP had posted, as if he did, he would know that this had to do with energy savings that new bios are set up with.

Overclock.net is an amazing resource to use, and they do give tips on how to tweak bios settings to avoid something like what the OP has experienced, but its a bit ignorant to assume he hasnt already been to the site.

[Plasmon]

That's strange, shouldn't the SpeedStep recognize that you were in a program that heavily uses the CPU and keep it clocked at your OC setting? If not then it's kind of failing at doing it's job.

Is he experiencing a special case or does SpeedStep often throttle down when it shouldn't?

Does SpeedStep for Sandy Bridge systems more accurately maintain the high clock speed during games? Because if it does work like it's supposed to then it's better not to disable it so that you can generate less heat and also save power when you're idle.

[Deleted]

Does SpeedStep for Sandy Bridge systems more accurately maintain the high clock speed during games? Because if it does work like it's supposed to then it's better not to disable it so that you can generate less heat and also save power.

Not sure, but C-State has caused some problems in some machines in the past. Notably - its been known to interfere in certain cases with high-bandwidth SSD transfers; but I've seen nothing globally consistent. Its mainly visible in benchmarks - because transfers very (very) briefly slump and then pick back up again, not the sort of thing a human would notice, nor would common programs display it because they don't sample frequently enough.

Its not impossible that one or both of the power management features isn't quite sure exactly which mode to sit in - which may cause a lot of power condition changes (which will interfere with performance).

[Cilraaz]

Does SpeedStep for Sandy Bridge systems more accurately maintain the high clock speed during games? Because if it does work like it's supposed to then it's better not to disable it so that you can generate less heat and also save power when you're idle.

Yes. Sandy Bridge uses a newer implementation of SpeedStep, which has shown better results. With all pre-Sandy Bridge Intel chips it was suggested to disable C-States when overclocking anyway. The OP essentially just explains correcting a bad overclock.

[Plasmon]

If it's throttling down below stock speed then does this not also apply to everyone using first generation i5/i7 rather than only overclockers? If he's having Speedstep take down his speed to 1.5GHz, then if he was running his multiplier and BCLK at stock speed wouldn't he still experience the same throttling issue?
It wouldn't make sense to me for there to be something about overclocking that triggers poor SpeedStep behaviour that wouldn't exist normally at stock.

[Cilraaz]

If it's throttling down below stock speed then does this not also apply to everyone using first generation i5/i7 rather than only overclockers? If he's having Speedstep take down his speed to 1.5GHz, then if he was running his multiplier and BCLK at stock speed wouldn't he still experience the same throttling issue?
It wouldn't make sense to me for there to be something about overclocking that triggers poor SpeedStep behaviour that wouldn't exist normally at stock.

It's a "problem" with the initial version of SpeedStep and the fact that WoW isn't actually heavy CPU utilization. So WoW alone wouldn't trigger it to step the entire way to the top.

[Bassman]

Op, you mention, "cpu utilization never reached 100%".

My question to you is why do you want 100%? If your cpu is running at 100% usage, it's very possible it is then unable to process everything you're asking efficiently and in such case bottlenecking your GPU. Whilst I'm not addressing your other questions, this stood out as backward thinking, so I wanted to point that out.

Now GPU's, we love to see high numbers. A classic case of cpu bottlenecking is (in game) very high CPU usage and low GPU usage. Usually resulting in very low fps. My i7-930 (oc'd to 3.74ghz) and gtx 470 will show 18-20% CPU usage and 88-99% gpu usage in game, depending on whats going on. I run ultra settings, dual monitors, often with a bajillion web pages up on 2nd monitor, maybe a baseball game over the internet radio, or a music dvd playing, etc.