View Full Version : Cool Book Users

Jan 6, 2010, 10:55 PM
Hi Everyone

A very Happy New Year to all of you.

Just a quick question around Coolbook usage. I have the software and a licence for it, installed on my MBA Rev B.

Somehow I don't think I have ever been able to get it to work !

Could anyone help with the steps post installation in layman terms ? Do you know a video somewhere that takes a user through it step by step ?

1. How do you set the various speeds and voltages,
2. How do you save the combinations
3. Then how do I use once I have set them
4. Does the software automatically recognise that you have shifted from Power to Battery and choose the settings set for battery ?
5. It says experiment and find the right combination for yourself, which might cause a crash if the comibation is poor, when the crash happens what's the risk of lossing data/corrupting the OS ?
6. Whats the B1/B2 click box for ?

Your help will be useful for me and possibly others to use the software more effectively.

Thanks in advance.


Jan 7, 2010, 07:05 AM
Re: #1-3... follow the instructions in the Coolbook Manual (especially the sections labelled "Setting a frequency / voltage" and "Saving settings").

Re: #4... Yes, it knows when you are on AC or battery.

Re: #6... B1/B2 allows you to set the very low frequency/voltage pairs, which would generally only be used in the battery set of pairs.

Re: #5...

The point of testing using the CPUTest utility (the separate app, not the built-in test) is to make sure that the pairs you select are stable. That way you won't crash during real system usage. I've been running CoolBook Controller for a long time, and have never had a crash. You must be patient, though, and actually take the time to do full tests!

Keep in mind that heat (power) is generated linearly with the frequency and with the square of the voltage, so that's why managing both is important; that's also why focusing on voltage is key. The formula is P = C x V^2 x F (Power/Capacitance/Voltage/Frequency).

The key to using CoolBook effectively is finding the "magic" pairs:
a. Lowest voltage for highest frequency the chip supports
b. Highest frequency for the lowest voltage the chip supports

Once you find the "magic" pairs, you can set a number of "in between" voltage/frequency pairs

Each CPU is unique, you must test yours to find your "magic" pairs.

For my system, this is what I found/use:

CoolBook settings:

MBA 1.8GHz 128GB SSD

800MHz 0.9000V
1200MHz 0.9000V
1400MHz 0.9000V
1600MHz 0.9000V
1800MHz 0.9625V

600MHz 0.9000V
800MHz 0.9000V
1200MHz 0.9000V
1600MHz 0.9000V
1800MHz 0.9625V

Throttling level: High
Thermal limit: 85C

"Base" Pairs (found by testing):
1600MHz 0.9000V [highest frequency for lowest voltage]
1800MHz 0.9625V [lowest voltage for highest frequency]

I then set smcFanControl to keep the minimum fan speed at 1800rpm when on battery, and 3200rpm on A/C. Those exceed the default minimum speeds, but it's far easier for the system to stay cool than to get hot and cool back down. I chose those fan speeds because they are just barely audible (to me; your ears may be better or worse). smcFanControl does not limit increases in fan speed, it only adjusts the minimum.

Jan 7, 2010, 07:47 AM
It just looks too complicated and too much work?
Is it actually worth it?

Mr. Zarniwoop
Jan 7, 2010, 08:40 AM
It just looks too complicated and too much work?
Is it actually worth it?
It's not actually complicated, it's just not obvious. Once you understand it, it takes about 15 minutes of tinkering (and crashing) to find the optimal voltage settings, and then you forget about it and the laptop runs much cooler. I installed it originally because Skype video would cause a core shutdown. The other thing people complain about is YouTube videos.

If you haven't done so, install the pre-release Adobe Flash Player 10.1 (http://labs.adobe.com/downloads/flashplayer10.html) because it significantly reduces the amount of CPU any Flash (like YouTube) application uses, which in turn keeps your MBA much cooler as well.