Overclocking AMD64 and using AMD Cool 'n' Quiet

circle55

circle55

circle55

Associate
Joined
26 Oct 2006
Posts
13
I've read some conflicting information on enabling AMD's Cool 'n' Quiet on overclocked AMD64 processors.

Some say that if you overclock your processor, you should have Cool 'n' Quiet disabled. Some say it works fine on overclocked processors, and helps keep temperatures down. I never really went too much into this argument, but lately I've become more interested in overclocking myself, and wanting to know what the facts really are regarding this. A friend of mine told me that he's been running Cool 'n' Quiet on his overclocked AMD64 3400+ for more than a year smoothly with no problems or issues whatsoever.

He reports that Cool 'n' Quiet brings down his CPU multiplier to 5X from its max of 11, and reduces the Vcore when he is not needing the full speed of his system. When he is gaming, or running other intensive applications, the multiplier goes back up to its default max of 11X, and the Vcore goes back up to his overclocked settings and he gets the full overclocked performance. He has run benchmarks, (SuperPi, 3DMark06, etc) and has noticed almost no difference in performance either with Cool 'n' Quiet enabled or disabled. The only notable difference has been in temperatures, which he has found to be cooler while gaming with it enabled.

What are your opinions on enabling or disabling Cool 'n' Quiet with overclocked processors? If some say you shouldn't enable it, exactly why is that, since some report that it runs smoothly without problems, and may even keep your processor cooler and save on power consumption?
 
Last edited:
CrazyMonkey said:
I would turn off the Cool N Quiet if you are overclocking.
Click to expand...
Why exactly? If some are reporting the same performance with it on, along with the benefit of better and cooler temperatures with less power consumption, then why should it it turned off? :confused:

I can understand turning it off while you're changing and setting your optimal overclock settings, but once you fix your settings and achieve your desired overclock, what's wrong with turning Cool 'n' Quiet on after that?
 
Last edited:
A lot of motherboards will revert back to the default processor settings when cool and quiet is turned on. It also doesn't just use 5x and max multiplier but also intermediate multi's with different voltages which can cause stability problems that won't show up under full load. I use a program called RMClock utility which does the same thing as C&Q but lets you choose the voltage for each multi from 4x upto the max multi of the processor. (4x multi only works with the HTT multi set to 4x or lower)
 
Stability CAN be majorly affected by having C&C enabled. It's best to clock with it off - if people are worried that their temps are too hot, they shouldn't be overclocking anyway without a better heatsink.
 
Ive got my A64 3000+ running at 2.40 ghz and have never had any problems with cool and quiet being turned on. Needless to say Ive turned it off recently so it doesnt start changing the cpu speed when Im in mid game :eek:
 
For moderate/small overclocks its less of an issue than for larger overclocks. If you keep the default max multi and default vCore, and stray only a few mhz from stock then there shouldnt be an issue.
CnC drops the vcore and multi in a linear fashion depending on system load. Once the system is loaded again, the default multi and vcore for the chip is set again.
This can cause an issue in 2 ways. Firstly, if you drop the multi to push the FSB/memory further CnC will restore the chips default. eg - 3700 running 11*. Drop to 9* and run 300 FSB for 2.7ghz. Now, CnC kicks in, drops the vcore to 1.1 and multi to 5 (at the lowest "idle" settings). CPU's now at 1.5ghz, still running at 300 FSB. When the CPU's loaded again, the multi is set back to default along with the vcore. CPU's now running 300*11 which is 3.3ghz. Ouch!

Secondly, the multi and vcore are dropped linearly. Overclock often isnt linear with respect to voltage/speed increase. Chances are you'll reach a point where the CPU isn't stable at a given voltage or vcore.
 
Its a real deterrent to overclocking in the BIOS. Who wants to have their PC chuntering away at full bore the whole time? Intel processors don't seem to have any trouble with throttling while overclocked in the BIOS. I just use AMD overdrive when I game.
 
Depends how happy your board is with Cool n Quiet and how well it works. I have Cool n Quiet disabled in the bios and use an application called PhenomMsrTweaker which enables it again as my board won't do Cool n Quiet when overclocked. Works fine and I've had it running for over a year now with no problems whatsoever.

I recommend leaving it completely disabled as you set up your overclock then enable it again and see if you can get it to work afterwards. It's worth using it if you can because it should save some power, especially if, like me, you leave your computer idle a lot.
 
It should be off if your doing any serious overclocking.
Especially if raising the FSB.

The multi's and voltages will be wrong if the FSB isn't 200.
You will get plenty of blue screens at low loads.

If you are worried about power consumption DO NOT OVERCLOCK


edit: OOPS it's a necro thread
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom