I've put off overclocking my mac since last year, but tonight I tried it and it seems to be doing okay so far. I have a Mac Pro with dual 2.8GHz Xeons that are now oc'd to 3.2GHz. It's hard crashed once, froze one time, but I believe with smcFanControl properly adjusting fan speeds I can stabilize things. I've set the fan speeds as follows:

CPU_MEM: 1500rpm
IO: 1500rpm
EXHAUST: 1000rpm
PS: 1000rpm

iStatPro indicates my cpu's are hovering between 37-40C, and my memories don't get above 50C. Without oc and with OS X's default fan settings, memory temps can get to 80C while crunching! Not everything is peachy... the overclocking tool makes everything in the system faster, including the clock. So I have to rely on my wrist watch or my cellphone for that. It does seems faster at crunching, but I won't be able to tell until later. I was averaging 8000+ credits a day (on a good day) on the Mac Pro, we'll see how the oc will affect that.

Update: those fan settings may be good for the hardware, but it's not for the hearing... it gets a bit loud. And it froze the computer after two hours or so. I have to play around some more with the speed settings.

Update: those fan settings may be good for the hardware, but it's not for the hearing... it gets a bit loud.

You don't want a jet engine next to your head?

---

Doesn't expecting the unexpected make the unexpected the expected?
If it makes sense, DON'T do it.

You don't want a jet engine next to your head?

Nah, I'll settle for hair drier :)

Alberto, I have used the ZDnet tool for most of the past year on my MacPro, same config as you, you can put the fans down to 1000rpm and everything is fine. One word of warning remove the dust bunnies every 8 weeks or so and you shouldn't have any problems.

---

Mars rules this confectionery war!

SATAN, I can't seem to run at 3.2GHz for extended periods without crashing. I've throttled down to 3GHz and lower fan speeds, and that seems to be much more stable. I've left my mac running at home so when I go back I will see if all is still well. But would you know if there's a fix to the accelerated clock, or is just a fact of life for an oc'd mac?

I take it, if you've had the same experience as me, you end up with Kernel panics as soon as you try to set the speed. I do not know any way around this apart from keep trying, I know that isn't the answer your looking for but it is the best one I know.

I have managed to have My Mac Pro running constantly at 3.241GHz. Using SmcFanControl, I set the CPU-Mem to 1000rpms along with IO and Exhaust.

One thing I did try was to run the machine at 3.0GHz for a few days, then gradually build up the over clock.

Over all though it seems that each machine is different.

---

Mars rules this confectionery war!

Just one comment: ony use it for cunching with Mac Pros 2008 and 2009.

With the 2006-2007 model, the FSB clock is directly linked to the Real Time Clock and the time is then wrong, which can cause problems if you use automated jobs (crons) like Time Machine.

Just one comment: ony use it for cunching with Mac Pros 2008 and 2009.

With the 2006-2007 model, the FSB clock is directly linked to the Real Time Clock and the time is then wrong, which can cause problems if you use automated jobs (crons) like Time Machine.

The FSB clock is also directly linked on the 2008 Mac Pro. SO after 6 hours, your computer is 1 hour ahead.

---

Mars rules this confectionery war!