fan runs faster after sleep but then slows to normal. Problem?

When your computer sleeps and the fans spin down, heat can build up so that when it does come back to life it also may be warm enough to need to get air moving. And because in some situations it does so as a preventative measure if thermal sensor readings are not available.

Nothing to worry about. Totally normal. There was a firmware update back in.... Aug/Sept '07 to update SMC/EFI.

You also with that and FBDIMMs want to run SmcFanControl 2.3+ to insure the fans run around 800 rpm instead of 500-600 rpm to do a better job expelling and circulating air over RAM.

That is not for use on Mac Pro. Sorry, go back one squjare.

www.macupdate.com

Serious? All I do is type "SmcFan" into MacUpdate and get 2.3

http://www.macupdate.com/app/mac/23049/smcfancontrol

It puts an icon on the menu bar from which you configure the default and add any other profiles you need (default, low, medium, high, extreme) with different fan speeds (3 of 4 only).

It isn't an app as much as a background process. Can't believe it is unintuitive or that there is no readme.

I'd begin with setting a profile for 800-900 rpm for normal lite use and set one to 1100 and one to 1300. Around 1000 rpm is where I can detect the fan noise but not bothered by it.

You might want to check out "Temperature Gauge" in the App Store to get a detailed handle on what the internal temperatures are in your Mac. Then, you can create different fan speed presets in smcFanControl and watch what they do. The thing to keep in mind is that internal temperatures go up as the computer works harder and/or as the ambient temperature rises. So having a number of smcFanControl presets can prepare you for those variables. And it will continue to work when/if you upgrade to Lion.

i once said to use 800-900 rpm to start with as base

Hardware Monitor has been #1 but there are a number of those, iStatPro etc

The "operating temperature" is the ambient temperature of the air the fans are sucking in to cool the Mac. If the ambient temp is already 95º F, it's going to take a lot of air to bring internal part temps down.

Just pulled the panel off my retired MacPro 1,1. There's a CPU/RAM tunnel at the bottom with a fan in front and another in the back, whose grill work you can see. There's another fan at the front of the PCI slot area. And there's a fan in the top optical drive/power supply tunnel at the front of the power supply.

While smcFanControl sets the minimum fan speed, the Mac determines what the appropriate fan speed adjustments, if any, should be. I've wondered about that too and I think it's that the exhaust end of the tunnel should be sucking air faster than the intake end is blowing it in. As I understand it, the Temperature Gauge display shows the allowable range, and if a fan is running faster than the lowest speed, the green bar shows the actual speed.

I don't fully understand the range of temperatures shown for a given part either. I did some voluntary beta work on Temperature Gauge because the first versions weren't fully dealing with my 1,1 Mac Pro and what those readings actually were wasn't resolved. E.g., the CPU A Core is 157º and the Diode is 82º on my 5,1 Mac Pro right now, and as the Diode temp goes up, the Core temp goes down. I have to wonder if the Core measurement is a dynamic overheating shutdown point which goes down as other component temps go up.

I pointed to #1 Hardware monitor, and I think iStat has gotten better so they could be tied.

HW can alert when a sensor hits a reading.

Only that 800-900 is usually enough for replacement for lowest setting instead of the 499/599 that the system would use otherwise.

but it does sound too warm possibly.

FBDIMMs are essential to keep cool and aim for 70*C or less. 2006-2008

Cloggedf GPU cards and fan not working is another culprit (the X1900 was horrible and had to be removed and dust bunnies and to unclog the card's chamber, poor design. And was $399 of all horrible things.

Temperature Monitor is free version of HW w/o a couple features but also accurate.

When you say "the temp" there are dozens of places to read from as you found. And Apple does not get technical on such things. Even Intel is slightly mum and it is more complex than first appears (like the thermal max junction point and what an Xeon does). But those processors are designed to run at 55-70*C (I never use F for computers so I have to translate degrees). Idle you want to see anything under 40*C.

Newer hard drives, to save energy, are designed to run warmer (40*C) as even 5*C means saving $$ on cooling costs for systems and servers.

Odd that it is next to impossible to get good GPU readings which are very accessible under other platforms. And yet those have always it seems been an issue.

What you are doing is setting a new, higher base rpm. The system will still run fans faster if needed but it is easier to act preventatively if you know you will be doing something that generate heat. And change to a profile of 1200 or 1500 ahead of time - and leave it there to expel the heat before shutting down or sleep mode to prevent heat from staying inside or building up inside with fans off.