Intel Dynamic Acceleration

When details of Santa Rosa were released, one of the things that were new to the centrino platform was Intel Dynamic Acceleration. Now that Santa Rosa is widely available, I can't seem to find any more information or benchmarks about this particular feature.

BTW, for those of you who don't know, here's a description of it on Intel's website.

http://www.intel.com/products/centrino/duo/description.htm

This feature is available only on T7700, the T7500, the T7300 and the T7100.
Take a look at the last picture of the page: http://www.trustedreviews.com/notebooks/review/2007/04/17/Intel-Santa-Rosa-Revealed/p2

Does anybody know exactly how IDA works? When does IDA kick in? How much faster are we talking about?

 

You can read all about it in the Intel data sheet.

My own observation is that when one core is idle then the other may speed up by one clock step. For example, the 2GHz T7300 can temporarily run at 2.2GHz. This functionality needs to be enabled in the BIOS. A simple test to see if it is working is to run SuperPi. Without IDA I recorded 2M in 61s for a T7300. This improved to 56s with IDA enabled.

You should also watch out for the associated feature of dynamic FSB switching: Under low CPU load the FSB speed may be halved and you may see the CPU voltage drop (by 0.1V?).

The CPU info page of CPU-Z can show what is happening. However, because the refresh rate is many times slow than the changes in CPU operation you may need to watch for a minute or two to see evidence of the dyanmica CPU changes.

John

 

Coolme your quote explaines it very well what more do you want to know? The 7250 also supports. Even though it sounds like a speed boost its main function is to reduce power drain. It will shut one core down and for example boost a 2Ghz to 2.2Ghz It will give a little more performance when used but a lot of power savings.

 

I had fiddled around with the bios in order to reduce the slight whining noise i get from my dell and I initially thought that the IDA was just another "throttle back the CPU clock". However i was noticing slow super pi times compared to other t7100 users and tried putting it back on and noticed a huge improvement. As others have stated, it basically forces one core to work like a donkey and the other puts up its feet.

 

So is it an extra 20mhz to the bus speed (200mhz) or 200mhz extra mhz to the cpu frequency for all processors that support IDA?

Also, will it use the highest multiplier voltage as default voltage during IDA mode?

 

It adds a multiplier does not increase bus.


When Santa Rosa detects that only a single core is being taxed, and the second core drops to a sleep state of C3 and below, it will activate a special Turbo Bin, which is essentially an additional multiplier level above the processor's official rated limit to boost that particular core performance in that application. In short, Santa Rosa overclocks one core, while it downclocks the other in order to achieve better performance in single threaded applications while staying within official rated TDPs.

 

That's how I've understood it from Intel's site - overclocking one core for single-threaded applications. And the RM CPU Clock utility has been reporting my T7500 running at 2.39 GHz at times. So the next question is, can you set it to dynamically accelerate one core at all times? Using almost exclusively single-threaded applications, it seems that would be beneficial to me.

Question for banselby2a: Did disabling IDA eliminate the noise from the CPU? If so this may be a better solution than disabling C4 in RMClock, at least for power-saving times. Course when I disabled IDA and SpeedStep my BIOS ran slow as molasses in January, but that could've been because of the SpeedStep part.

 

I don't think so but am curious as to exactly why you want to? That is exactly what IDA does, and does faster better and safer (TDP) than you can?

 

Hmm.. that must explain this



I've also seen it go up to 2.3 ghz.

 

Yes? And Your Bus speed is 200Mhz, What is your question?

 

I mean that I didn't know it was Intel's dynamic acceleration that was overclocking the multiplier from the stock setting. It was one of the features of santa rosa that I overlooked when reading about the chipset.

I had a few threads I posted asking why it was overclocking and no one brought this up until now.

 

Quotes don't count towards 10 chars, even when they're alot more than 10 chars.

 

Ha Ha, I guess I am saying if you are doing that (single threaded) the CPU will do it for you already. When it doesn't it is for a reason that if you had forced to be 1 Core you would loose all benifit as 1 Core would be forced to do all the work. Giving up the entire 2nd Core for 200Mhz is likely to lower total CPU computing power. Let CPU do it.