Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

seveej

macrumors 6502a
Dec 14, 2009
827
51
Helsinki, Finland
I used to think of it as a vacuum cleaner when I owned a dual 1.25, nothing could be done even by replacing the fans in it to quiet it down and it still got hot as hell.

I still have one, sort of.
http://www.everymac.com/systems/apple/powermac_g4/specs/powermac_g4_1.25_mdd.html
It looks like an MDD, but it does not sound like an MDD. In fact more like a Digital Audio.

I also have a 20" Cinema Display (ACD, not Alu) to go with it, and the design, while not timeless, will definitely be respectable and distinct forever.

RGDS,
 

ActionableMango

macrumors G3
Sep 21, 2010
9,613
6,909
Nope.
I was a bit concerned first as well, but I saw similar differences in the mac fan control thread. I guess its becouse the CPUs are in line, and the rear cooler takes in warmer air.

The reason why I think it's odd is that everyone else has "CPU A" as the hot one. Your "A" is 7 degrees cooler than "B".
 

Objectivist-C

macrumors 6502
Jul 1, 2006
443
27
Could someone with an X5690 in a single-CPU Mac Pro 5,1 do me a favour and tell me what peak temp you hit while running the Prime95 torture test (ideally with hyper-threading enabled)? Thanks!
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
Could someone with an X5690 in a single-CPU Mac Pro 5,1 do me a favour and tell me what peak temp you hit while running the Prime95 torture test (ideally with hyper-threading enabled)? Thanks!

For temperature comparison, you need a full picture (e.g. ambient temperature, and fans speed, etc). Just comparing the max temperature has little meaning.
 
Last edited:

MacUser2525

Suspended
Mar 17, 2007
2,097
377
Canada
Could someone with an X5690 in a single-CPU Mac Pro 5,1 do me a favour and tell me what peak temp you hit while running the Prime95 torture test (ideally with hyper-threading enabled)? Thanks!

I have a couple of w3690 coming in a couple of weeks for my machines, if no one has done it by then I will.
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
If he don't mind to use W3690 as reference, then I've done this test before, and has the record
P95 low fan - clean.png
 

Valdaquendë

macrumors regular
Nov 7, 2018
113
48
Oregon, USA
This thread has touched on 'normal', 'safe' and 'maximum' CPU temperatures. If you came to this thread (as I did) in a quest to find out what these temps are, with regard to the Xeon family, the following may be of help.

As h9826790 pointed out, all of the operating norms posted here are well within the Xeon's range. 'Normal', of course, varies for each user, so unless a reference point is set for comparison (like "idling with MacOS-only running in a room with ambient temperature of 65˚F.") determining 'normal' is next to impossible. According to Intel's page on Xeon thermal management:
"Intel can't give a specific operational temperature range of an Intel® Xeon® Processor because it will depend on the maximum performance of the heatsink used [and] the way the fans are controlled in a system (which can vary the performance of the heatsink)."
Nonetheless, Intel gives ≈75˚C. as a 'maximum case temperature' in their table of Xeon thermal characteristics.

A Puget Systems review, based upon their in-depth studies of the operational thermal characteristics of the Intel Xeon family, made the following observations:
"We know from both experience and explicit testing that modern Intel CPUs (at the very least Sandy Bridge, Ivy Bridge, and Haswell) can run at their maximum Turbo Boost frequency all the way up to 100 °C. While there may be a tiny performance difference between a CPU running at 30 °C and one running at 95 °C, our testing has found that the difference is minuscule. In fact, even after running benchmarks dozens of times the difference is so small that it is essentially nonexistent."
and:
We were very surprised when our testing showed that while the minimum CPU load frequency started to drop as soon as the CPU hit 100 °C, the average CPU frequency didn't drop by more than .1GHz until the CPU was overheating more than 30% of the time. In fact, Intel CPUs are surprisingly good at being able to handle this much heat with such a small reduction in the average frequency.
concluding:
For the average system, our rule of thumb at Puget Systems is that the CPU should run around 80-85 °C when put under full load for an extended period of time. We have found that this gives the CPU plenty of thermal headroom, does not greatly impact the CPU's lifespan, and keeps the system rock stable without overdoing it on cooling. Lower temperatures are, of course, better (within reason) but if you want a target to aim for, 80-85 °C is what we generally recommend.

I set my fan controls to keep my CPU-A core temp below 92˚C. when doing extended Handbrake encoding or other CPU-loading tasks.

I hope this information is useful.
 
Last edited:
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.