Cooling the Mac - parallels makes it run hotter?

G

GregA

Junior Member
Hi,
I've sold 2 family members on Parallels. I can't use it myself, but will when I've got an Intel Mac.

I was commenting the other day on how hot the MBP is. It doesn't burn, but it's very uncomfortable to work with if you're typing and your left hand is so hot. I had just decided not to buy a MBP until they'd solved this issue (I know they run hot sometimes).

Anyway, I shutdown Parallels on this machine, and it's been running cooler. I don't know the specifics yet - perhaps it's because the machine will sleep when Parallels is closed, perhaps it switches to single processor if parallels isn't around - I really don't know.

I'm wondering what I can do to give the Mac a chance at staying cool. Could anyone tell me the known issues and work arounds? Any changes in the upcoming version? Recommendations?

(I did a quick search, didn't find much... maybe I'm blind though).
 
Many months ago Apple released a firmware patch that managed the internal fans better - check your firmware version against the Apple release numbers. It helps, but what worked for me was to buy a platform the laptop sits on. The platform has two small fans in it. It takes very little air movement to cool the laptop. It also tips the keyboard a bit to provide a more comfortable typing angle. I was going to get one anyway just for the improved typing, so this was not an inconvenience and the system stays cool. It is powered by a USB connection.

Alternately you can suspend Windows when your not using it. It wakes up quickly and everything is right where you left it. Because Windows is always doing something it is always demanding CPU time and that translates to heat.
 
So increase the internal fans, or add fans to the base.
Am I right that this is a problem because Parallels is running?

The annoying thing is, very often the windows/parallels is in screen saver mode. I wonder if I can set Windows to auto-sleep (within parallels) or something similar.
 
GregA said:
So increase the internal fans, or add fans to the base.
Am I right that this is a problem because Parallels is running?

The annoying thing is, very often the windows/parallels is in screen saver mode. I wonder if I can set Windows to auto-sleep (within parallels) or something similar.
Click to expand...

Screen savers in Windows just burn CPU time. Set the screen saver to none and save your clicks for useful things.

Apple's Intel powered laptops get hot. It's been a problem since long before Parallels came along, but because Windows never sleeps it keeps the system busy and warmer than if it were not running at all. In fact if I shut Windows off at night my laptop keyboard and surfaces are actually cool to the touch in the morning. It isn't Parallels that is doing it - I run Solaris Unix in Parallels and it does not create the heat Windows does.

For efficiency do try to use OS X applications rather than Windows applications - browsers and email being two of the busiest, most used. Avoid and upgrade away from Rosetta supported applications in favor of Universal applications. Use NeoOffice rather than MSOffice, for example. Rosetta is a wonderful and effective stop gap, but it is very cpu intensive. Avoid running on battery if you can.

If you're not using Windows then suspend or pause it. Suspending it will restore cpu and memory back to OS X while pausing it will roll back on required CPU time but not memory. Either method restores quickly.

Don't play audio CD's - bring them into iTunes and play them there.

Keep your screen brightness as low as possible. It is powered by stuff under your keyboard and it gets hot.
 
dkp said:
Screen savers in Windows just burn CPU time. Set the screen saver to none and save your clicks for useful things.
Click to expand...
Agreed. As I said, it's not my machine, but I'll change that when next I'm there.

I would be very interested in having the windows screen-saver automatically activate the "pause" option in Parallels. I'll have to request it as a future feature...?

Speaking of "pause" vs "suspend" - I see that the pause button on the toolbar suspends the machine? Is there a button on the toolbar that does the same thing as the menu option "pause"?

Apple's Intel powered laptops get hot. It's been a problem since long before Parallels came along, but because Windows never sleeps it keeps the system busy and warmer than if it were not running at all. In fact if I shut Windows off at night my laptop keyboard and surfaces are actually cool to the touch in the morning. It isn't Parallels that is doing it - I run Solaris Unix in Parallels and it does not create the heat Windows does.
Click to expand...
I know it's not parallel's specifically - but Microsoft isn't going to change Windows to help us here. Parallels may have a way of auto-pausing Windows if it hasn't been clicked on in 2 minutes, or even unpausing for 30 seconds every 30 minutes so any applications can update...

I agree that the Intel laptops get hot - but with regular (non Windows/parallels) use the heat is okay. This is not, unfortunately.

[QUOTE[If you're not using Windows then suspend or pause it. Suspending it will restore cpu and memory back to OS X while pausing it will roll back on required CPU time but not memory. Either method restores quickly.[/QUOTE]
Restoring from pause is instant, suspending takes 30 seconds (though today it was about 3 minutes.. not sure what's going on but hopefully the re-install has helped).

So either will allow my computer to cool right?

Keep your screen brightness as low as possible. It is powered by stuff under your keyboard and it gets hot.
Click to expand...
I hadn't heard this at all.

Thanks for all the advice
 
My vote would be a Preference option to automatically PAUSE the VM when the application is hidden or in the background. Now, not everyone would want that, especially if they have Windows doing something and want that action to continue, even in the background. But, for the rest of us users, an Auto-Pause option (as a preference) would be highly desireable.
 
I agree auto-pause has merit as a option. In my case Windows is used primarily to read office mail with Outlook (Web mail) in IE, so it wouldn't work for me. I also use Virtual Desktop for OS X and have several virtual desktops active that I move between very frequently, so auto starting/stopping Parallels would probably not be practical. I do manually suspend Windows when I'm on batteries. The laptop cooler I bought and the firmware upgrade do a good job for me.

I just now recall that when I first got the MacBook Pro I purchased so snap-on half spheres from the Apple store to provide a bit of lift to the rear of the laptop and I noticed immediately that the laptop ran much cooler with those attached and providing air flow under the case than when it laptop lay flat on the desk.
 
neosublime said:
Better than SMC is FanControl
Click to expand...

I just installed the tool from Eidac - i turned off the power to my external fans and I'm surprised at how cool the keyboard has gotten. The fan speed is running at around 2000 rpm. The CPU heat didn't drop all that much, but the heat is getting out of the system and keeping the case temperature comfortable.

I'll try the one you suggested next. What feature(s) did you prefer?
 
I always use a metal plate as an extra heat sink under my MacBook Pro and rarely hear the fans go on

I use external keyboard and mouse


Hugh W
 
Question on fan control. Does it automatically adjust settings? Is there a way to revert to default if it messes up?
 
Fan control sets the minimum speed, not the max speed. OS X will set it to what ever speed it deems appropriate so long as it is as fast or faster than the Fan control speed. It's pretty hard to hose a system with too much cooling unless you're on batteries and they're close to dead and the fan is blowing too hard. It will shorten battery life.
 
Just a quick note as a support engineer not only does using a 3rd party app to adjust your hardware reduce the life of your hardware it can in some cases void the warrenty !!

I have read a few cases but do know one person whos fans lasted just over 2 months and then the bearings went !! The heat from this damaged the logic board and it worked out cheaper in the long run to buy a new MB Pro !!

Just a warning :)
 
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auto-pause: a big +1

however...

parallels STILL consumes ~7% CPU when paused and hidden. This means whatever you do on a laptop parallels cannot properly reduce the CPU when not needed (and your battery will drain even when paused etc)! It should use *no* CPU when paused and hidden...
 
Ok so I installed fan control but don't understand the options. What should I set to help with Parallels and cooling?
 
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