SpeedStep causing FPS spikes

Hey everyone,

I bought a Dell Vostro 1500 a few weeks ago, and although I'm very happy with it, there is one issue that keeps irritating me.

Basically, the 'SpeedStep' feature of the CPU keeps kicking in when I'm playing games, causing my CPU to decrease to 1/2 speed and giving me stupid low FPS spikes. This only happens when running on batteries.

From my understanding this should not take place when the CPU usage is high, and it seems to happen at frequent intervals, about 10 seconds apart, for 15 seconds or so. It's quite annoying because it causes low fps spikes during gaming.


I've tried disabling SpeedStep in BIOS - Worked in that it stopped the spikes because my CPU didn't throttle itself anymore, but it was stuck at 1/2 speed permanently. I also tried SpeedSwitchXP, putting everything on High Performance, Always On, No Power Saving etc, and disabling EIST etc. Although it means my proc runs at 100% when on mains, it still downclocks in the same way when on batteries.

This can't be a temperature issue because when the laptop is in the same position when on mains, it works perfectly, and to be honest, it doesn't get that hot anyway (nor does the temperature sensor show alarming heat.


This happens in Vista and Windows XP, even after tinkering for hours with the power saving and SpeedSwitch settings.


The CPU shouldn't be downclocking during high CPU usage, regardless of it running on batteries, but for some reason it does, and it causes crappy low FPS spikes that makes some games virtually unplayable unless plugged into a wall socket.



Any suggestions or similar experiences? I've been battling with the issue virtually since I got it, did a few hundred google searches (that pretty much recommend the same thing), but nothing seems to make any difference at all.



Thanks in advance...

 

You're looking in the wrong place for the solution as you've mis-diagnosed your problem!

SpeedStep is a feature that, as you rightly pointed out, affects the CPU, but games don't only use the CPU! Your GPU also has a SpeedStep like feature. Your ability to adjust that depends on the card and your drivers, but that is the root of your problem.

If you can adjust the GPU settings to disable its SpeedStep (Nvidia calls it PowerMizer) you'll see your performance go to normal and your battery go to nothing

 

IMHO:

Plug in when you're gaming. This would reduce the cycles and wear on the battery, as well as giving you the desired performance.

 

No offense, but I have a pretty good idea of WHAT it is doing, I just don't know WHY.

Powermizer is disabled in nVidia control panel.

In addition, by running my game in a window and having CPU-Z open I can see the real time CPU speed. The FPS drops coincide exactly with the drop in processor speed, and visa versa.

 

Are you running it on max power?

 

Like I said, the ability to adjust PowerMizer depends on your driver!

If you're on Vista you can do it in Vista's power control panel. On XP a lot of drivers have PowerMizer's control panel disabled, but it is ENABLED (so you can't switch it off). If you're on XP then you need to get a PowerMizer driver from laptopvideo2go.com to adjust that...

The proof is in the pudding... You said yourself turning off SpeedStep didn't clear your problems...

 

If you find out anything let me know.

It drives me crazy with a few games...basically its both PowerMizer AND Sspeedstep causing the issues I watch them both downclock when playing older games. In Vista Powermizer is nowhere to be found, and RMClock is a no go in Vista 64. Its annoying that if I disable speedstep in bios the processor runs at half speed instead of running at normal speed. This is all on AC power as well its not a battery issue. I have been experimenting with Nibitor to change the active number of modes from 4 to 1 or 2 but I get video corruption after flashing the modified bios perhaps because Dell puts the two 8800's on one card.

I play Everquest, and the darn thing is almost nearly unplayable on my m1730 because of Speedstep and Powermizer...whereas I can play Crysis on almost all high settings at 1920x1200. Its crazy. I mean don't get me wrong I love my laptop but I shouldn't have problems with older games.

 

Please, can you read what I'm saying instead of what you think I'm saying? I have the option for Powermizer. I have chosen the 'disabled' option (ie max power all the time).

I clarified the OP. Disabling SpeedStep does stop the spikes, but my games run inherently slower because it makes the CPU run permanently at 1/2 speed. Infact, they run at the same speed as when the low fps spikes occur when it is enabled - COINCIDENCE!?

In addition, I also said that the FPS drops coincided directly with the CPU throttling.


Just to go over the problem one more time, here is the problem in easier to understand details:

ON MAINS POWER
No load: 6x Multiplier
Full load: 12x Multiplier

This gives a perfectly smooth and enjoyable gaming performance.


ON BATTERY POWER
No load: 6x Multiplier
Full load: 12x Multiplier for 15s, then 6x multiplier for 15s, in a constant cycle.



Does no one else see a problem here?

 

I'm leaning toward it being associated with older (more CPU intensive, less GPU intensive games).

For example in WoW (DX 8.0 game) these spikes are very noticable because the CPU throttling lasts for 10-15 seconds at a time, but in EVE Online (DX 9.0 game) the CPU throttling lasts for a split second only, you can check this yourself by running your game in a window with a copy of CPU-Z in view, and seeing if the FPS drops happen at the same time SpeedStep thinks you aren't using the processor (even when usage is >90-100% at FULL speed)


One suggestion I got from another forum is to put the game you are having a problem with at a higher process priority, can't try it though as I am at work