Overclock problem?

[Devilz]

I've overclocked my Q6600 from stock speed to 3.2GHz. Everything seems fine, voltages are alright as well. It shows at POST that its running at 3.2 but in windows it shows its still at 2.4 and in cpuz it core clock speed keeps changing from 2GHz to 3.2GHz. Here are the screenshots

In the second screenshot, you can see core speed is 2GHz

what can be the problem?

 

[SledgeDG]

For the numbers showing in CPU-Z : just go in your power options and set it to
High Performance.
I stumbled over that when I got my last (this) computer and saw those numbers fluctuating


Only Difference I have an Athlon and there it would rather fluctuate the multiplier than the core speed
-DG

 

[jimbonbon]

If you have C1E stepping enabled in the BIOS, make sure you disable this. This is highly recommended when overclocking for stability reasons.


J

 

[EzioAuditore]

Apart from C1E option, this can also happen when there's no need for such core speed i.e. it's also depends on the work load.
For eg. download RealTemp, open it and run the XS Bench (clickable button), you'll notice that core speed would have reached to highest i.e. 3.2 (which you've set) and after the benchmarking, it'll come down.

 

[jimbonbon]

Apart from C1E option, this can also happen when there's no need for such core speed i.e. it's also depends on the work load.
For eg. download RealTemp, open it and run the XS Bench (clickable button), you'll notice that core speed would have reached to highest i.e. 3.2 (which you've set) and after the benchmarking, it'll come down.

Good point, should have also mentioned this, i.e. Speedstep. This is more what the OP is talking about rather than C1E. Speedstep reduces your clockspeed dependant on load like you describe.

Personally when overclocking I disable both C1E and Speedstep, but this isn't necessarily a requirement, it just helps with stability at higher OC's. It does of course mean a slightly higher power consumption continuously, i.e. even when the CPU is not in use.


J

 

[Nemix]

@ Devilz

The answer is simple math.

The default FSB for a Q6600 is 267 Front Side Bus and the default multiplier is 9 which is 9 x 267 = 2403 or 2.4Ghz Default.

You have overclocked the FSB to 400 and the lowed the multiplier to 8 which is 8 x 400 = 3200 or 3.2Ghz.

Correct?

Now, Windows will always use the default FSB for your CPU (no matter what the overclock is) but use the modified multiplier value (weird but true) so Windows sees your CPU as 267 (default FSB) x 8 (modified multiplier) = 2136 or 2.13Ghz as shown in your Windows system information Q6600 @ 2.4Ghz 2.13Ghz.

Just to see if my answer is true, try going back into your BIOS and change the multiplier to 7 while keeping FSB at 400, boot into Windows and your system information should be shown as Q6600 @ 2.4Ghz 1.87Ghz.

End phrase, not to worry as long as CPU-Z shows your CPU is running at 3.2Ghz your overclock is successful. And the fluctuation in your CPU just means is going into low power mode (C1E in BIOS and Power Options in Control Panel > Minimum Processor State), it has nothing to do with the overclock as long as your system is stable.

 

[jimbonbon]

@ Devilz

The answer is simple math.

The default FSB for a Q6600 is 267 Front Side Bus and the default multiplier is 9 which is 9 x 267 = 2403 or 2.4Ghz Default.

You have overclocked the FSB to 400 and the lowed the multiplier to 8 which is 8 x 400 = 3200 or 3.2Ghz.

Correct?

Now, Windows will always use the default FSB for your CPU (no matter what the overclock is) but use the modified multiplier value (weird but true) so Windows sees your CPU as 267 (default FSB) x 8 (modified multiplier) = 2136 or 2.13Ghz as shown in your Windows system information Q6600 @ 2.4Ghz 2.13Ghz.

Just to see if my answer is true, try going back into your BIOS and change the multiplier to 7 while keeping FSB at 400, boot into Windows and your system information should be shown as Q6600 @ 2.4Ghz 1.87Ghz.

End phrase, not to worry as long as CPU-Z shows your CPU is running at 3.2Ghz your overclock is successful. And the fluctuation in your CPU just means is going into low power mode (C1E in BIOS and Power Options in Control Panel > Minimum Processor State), it has nothing to do with the overclock as long as your system is stable.

Whilst I would tend to agree with you that what Windows shows can be different from CPU-Z, if you see the screenshots in the OP, this is also showing the lower clocks in CPU-Z therefore we are definitely talking power saving or CPU stepping in this case.


J

 

[Solarstarshines]

Apart from C1E option, this can also happen when there's no need for such core speed i.e. it's also depends on the work load.
For eg. download RealTemp, open it and run the XS Bench (clickable button), you'll notice that core speed would have reached to highest i.e. 3.2 (which you've set) and after the benchmarking, it'll come down.

I can agree with this statement because the core speed buckles down if there is no need for it im running 3.22 ghz but if i look in my cpuz i am running much lower

this does makes sense because my pc doesnt have any lag or performance issues just as fast as the day i put it together

but like i show here it shows how fast i am really running vs the other readings and rated speed im actually running a little faster then the rated 3.22 shows im doing 3.3 3315 ghz

 

[Nemix]

It's simple, when the computer is doing nothing it'll try to save power.

Unless your disable C1E in BIOS or change Minimum Processor State to 100% in Power Options.

It has nothing to do with the overclock, as stated above. Generally it's better to keep C1E and Minimum Processor State at 5% as this helps reduce power when computer is doing nothing and also keeps your CPU cool and quiet thus prolonging the life of your CPU. But if you run into stability problems with your overclock then usually disabling C1E helps and if you just want to show your CPU at the highest overclock value at all times in CPU-Z then changing Minimum Processor State to 100% takes care of that.

 

[Wishmaster]

I would try getting things stable with C1E and SpeedStep enabled. 99% of the time you can. (Unless your really doing some heavy OCing)

Windows may also refer to the stock Multi for whatever reason.

So if you have a default Multi of x9 and set the OC at a 400FSB x8, Windows will show 3.6Ghz. (400x9) even though your actually at 3.2 400x8.

I've never really figure out why it does this sometimes.
Mines actually showing as it should.

Just go by what CPUZ shows at load. This is your true clocks.
Will at idle, Speed Steep and C1E will reduce Voltage and Multipliers to save power and lower Temps.
Its a good thing. No point the CPU running full bore 24/7 when it isn't needed.

 

[chev65]

@ Devilz

The answer is simple math.

The default FSB for a Q6600 is 267 Front Side Bus and the default multiplier is 9 which is 9 x 267 = 2403 or 2.4Ghz Default.

You have overclocked the FSB to 400 and the lowed the multiplier to 8 which is 8 x 400 = 3200 or 3.2Ghz.

Correct?

Now, Windows will always use the default FSB for your CPU (no matter what the overclock is) but use the modified multiplier value (weird but true) so Windows sees your CPU as 267 (default FSB) x 8 (modified multiplier) = 2136 or 2.13Ghz as shown in your Windows system information Q6600 @ 2.4Ghz 2.13Ghz.

Just to see if my answer is true, try going back into your BIOS and change the multiplier to 7 while keeping FSB at 400, boot into Windows and your system information should be shown as Q6600 @ 2.4Ghz 1.87Ghz.

End phrase, not to worry as long as CPU-Z shows your CPU is running at 3.2Ghz your overclock is successful. And the fluctuation in your CPU just means is going into low power mode (C1E in BIOS and Power Options in Control Panel > Minimum Processor State), it has nothing to do with the overclock as long as your system is stable.

The part in bold red is'nt exactly correct. Windows will use what ever you have set in bios for the FSB. Your math is correct but your analogy is not. Windows WEI also shows me at 4050Mhz or 4.05Ghz.

For instance right now I'm using a 9x multi,450 FSB clock or 1800QDR speed, for my FSB yet the default for my Q9650 is 333 or QDR of 1333/4= 333.25.

With C1E and speed step disabled you get the true CPU frequency in CPUz.

I might also point out that with this overclock which is rather stout, there was no chance of getting it stable without disabling those power saving features. This is a 12 hour Prime Blend stable overclock.

Although as Wishmaster pointed out it is possible to get a decent overclock without disabling those power saving features, there are limits to how far you can get with them enabled though.

 

[Nemix]

That's not a Windows system picture you have there. I know that on my system does not matter the FSB Windows will always use 200 as my FSB times the CPU multiplier. I know I could be wrong but I'm sorry you have not corrected me in any way.