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fs454

macrumors 68000
Original poster
Dec 7, 2007
1,977
1,824
Los Angeles / Boston
So I bought 4 gigs (2x2gb) of OWC brand RAM that came today. I don't recall the stock RAM temps(took it out, running just the 2x2gb), but iStat is reporting 52-54C on both memory modules. I haven't done any heavy work on these since I got them, just played some Line Rider and browsed the web and stuff.


Is this too hot or is it okay? It's the hottest thing inside my MP right now so seeing 50+C for the first time drew my eyes right to it.

thanks.
 

phjo

macrumors regular
Jan 8, 2008
149
1
There is no reason not to put back the two 1Gb stock module on botton riser I think but as for your temperature concern, I have the same...

Apple (Hynix in my case) original fb-dimms run a bit cooler than the owc 2Gb I installed (see barefeats as well), maybe because they are 1Gb instead of 2Gb.

Letting my 8 core work for BOINC right now, my dimm would go up to 75°C with the default fan speed, which is too much for my taste, and if you do serious computation, I would advise you (or everyone) to use smcfancontrol to speed up a bit the lowest speed of the cpu/mem fan (exhaust will be adjusted automatically so as to run 100rpm higher than the cpu/mem)

Temp are now about 42°C for the cpu (running 100%) and tops at 63-64 for the memory (original 1Gb sticks : about 56°C)

So yes, the temperatures you mention looks correct, and yes, the memory modules are by far the hottest part in the mac pro... (And I still don't understand the choices made for running the mem/cpu fan at so low a speed... move it up to 700 instead of 500 and you'll be fine, with no audible extra noise...)

phjo
 

netnothing

macrumors 68040
Mar 13, 2007
3,806
415
NH
Make sure you also post your Ambient temp so we can get an idea of how hot the air is.

I have the older Mac Pro, and just recently got 8GB (4 x 2GB) of OWC RAM. I added this to the stock 2 x 512 MB Apple dimms and 2 x 1 GB Crucial dimms. So I have all slots full.

I was concerned with the temps I was getting on the 2GB DIMMS from OWC, with ambient temps around 21 C (70 F), I was getting 68 C on outside 2GB dimms.

I emailed OWC techs and they said that you don't want to let the dimms get over 73+ C.

Couple of facts:

1) The 2 GB dimms will run hotter due to more chips on the dimm itself
2) The more dimms you put in will increase temps. In my case I have all slots filled which means a lot of heat.

I can tell you, with my fans running at the lowest settings, the temps get get up there without doing much.

If I run smcFanControl to bump of the CPU and Exhaust fans....the temps will come down. I just hate the fact that on a $2500 machine, Apple can't spin the fans up to keep the temps down. At least give me the option to set lower limits (without having to install some 3rd party utility).

-Kevin
 

netnothing

macrumors 68040
Mar 13, 2007
3,806
415
NH
and yes, the memory modules are by far the hottest part in the mac pro... (And I still don't understand the choices made for running the mem/cpu fan at so low a speed... move it up to 700 instead of 500 and you'll be fine, with no audible extra noise...)

phjo

phjo,

Do you run smcFanControl all the time? Do you have it run at startup and set the base speeds? What speeds do you set? Are you on a 2008 Mac Pro or the older model?

I've been hesitant to run smcFanControl all the time, but I do end up seeing high temps on my OWC 2GB dimms, even when I not doing anything much on the machine. I think it's just the fact I have all the slots filled and the ambient temp gets above 70F.

-Kevin
 

firstyearprof

macrumors member
Apr 16, 2007
52
0
My OWC Ram is hot too

Hi all,

I have 18 GB RAM now on my macpro. It seems a bit hot to me as well. One of the modules on A2 is at 71 Celsius WITHOUT my computer having done any work. I guess I need to bump up the fan. Is this a MacPro design problem or an OWC problem? My ambient temp is 22.7

Picture%203.png
 

firstyearprof

macrumors member
Apr 16, 2007
52
0
OK - I just downloaded and installed smcFanControl and bumped the cpu/mem fan to 630. The temp for the hottest module went from 71 C to 66 C . Still seems a bit hot to me.

Are there any problems with setting the fans to a higher rpm? Does 66 seem to hot to folks around here for a RAM module that has been basically idle?

Picture1.png
 

netnothing

macrumors 68040
Mar 13, 2007
3,806
415
NH
OK - I just downloaded and installed smcFanControl and bumped the cpu/mem fan to 630. The temp for the hottest module went from 71 C to 66 C . Still seems a bit hot to me.

Are there any problems with setting the fans to a higher rpm? Does 66 seem to hot to folks around here for a RAM module that has been basically idle?

Picture1.png

That one module does seem to be high, although I have 2 modules that tend to run hotter than the others.

Attached are my temps right now, with the fans at the base settings (for the 2006 Mac Pro). I'm not doing anything intensive on the machine. As you can see my high temp dimms are A2 and B2 (both 2GB dimms).

It's really amazing that I can use smcFanControl to bump up the CPU fan to 710....and it will drop RAM temps from 70C down to 61C in about 10 minutes. I'm still shocked Apple hasn't allowed users to up their min fan speeds to keep the machine cool.

-Kevin
 

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phjo

macrumors regular
Jan 8, 2008
149
1
phjo,

Do you run smcFanControl all the time? Do you have it run at startup and set the base speeds? What speeds do you set? Are you on a 2008 Mac Pro or the older model?

I've been hesitant to run smcFanControl all the time, but I do end up seeing high temps on my OWC 2GB dimms, even when I not doing anything much on the machine. I think it's just the fact I have all the slots filled and the ambient temp gets above 70F.

-Kevin

smcFanControl does not have to be running... and it looks like the settings are preserved after a reboot (but probably not a smc reset...)

So right now, smcFanControl is not running, but the settings still apply, with cpu/mem set to 700. Max temperature is now 65°C for the ram, 40°C for the cpu (mac pro working hard for boinc...)

If I let the mac pro to idle, the original fan speed would be ok, but it is stupid to let idle the mac pro, especially as I won't let it sleep...

phjo
 

netnothing

macrumors 68040
Mar 13, 2007
3,806
415
NH
smcFanControl does not have to be running... and it looks like the settings are preserved after a reboot (but probably not a smc reset...)

So right now, smcFanControl is not running, but the settings still apply, with cpu/mem set to 700. Max temperature is now 65°C for the ram, 40°C for the cpu (mac pro working hard for boinc...)

If I let the mac pro to idle, the original fan speed would be ok, but it is stupid to let idle the mac pro, especially as I won't let it sleep...

phjo

Ahh...so smcFanControl sets the min and doesn't need to be running huh? Interesting. I thought I read about that somewhere but had forgotten. I think it survives reboots, but not shutdowns.

So if I set the CPU fan to 710....that is essentially like setting the min speed. Might have to try that. I see where is automatically kick up the exhaust fan to 100rpm higher than the CPU fan.

-Kevin
 

netnothing

macrumors 68040
Mar 13, 2007
3,806
415
NH
smcFanControl does not have to be running... and it looks like the settings are preserved after a reboot (but probably not a smc reset...)

So right now, smcFanControl is not running, but the settings still apply, with cpu/mem set to 700. Max temperature is now 65°C for the ram, 40°C for the cpu (mac pro working hard for boinc...)

If I let the mac pro to idle, the original fan speed would be ok, but it is stupid to let idle the mac pro, especially as I won't let it sleep...

phjo

So I'm now setting the CPU min with smcFancontrol to be 610rpm (about 100rpm higher than the default). This in turn bumps up the Exhaust fan to 710rpm, again about 100rpm higher than default.

So far, I'm seeing temps drop by up to 10C depending on the ambient air.

-Kevin
 

Bastich

macrumors regular
Jul 22, 2002
100
0
Have you tried moving that "hot" module to another slot? Might be the location, and not the memory itself.

:cool:
 

Infrared

macrumors 68000
Mar 28, 2007
1,714
64
So I bought 4 gigs (2x2gb) of OWC brand RAM that came today. I don't recall the stock RAM temps(took it out, running just the 2x2gb), but iStat is reporting 52-54C on both memory modules. I haven't done any heavy work on these since I got them, just played some Line Rider and browsed the web and stuff.


Is this too hot or is it okay? It's the hottest thing inside my MP right now so seeing 50+C for the first time drew my eyes right to it.

thanks.

Looks about right. Not doing much, room in the low 20s C,
with stock Apple RAM (1GB + 1GB), iStat pro reports these
temperatures:

temps.png

Curiously, I don't see what is obviously a GPU temperature in
that list. Is it possible to get the GPU numbers for a Mac Pro?
 

supercooled

macrumors 6502a
Sep 6, 2007
737
1
Ahh...so smcFanControl sets the min and doesn't need to be running huh? Interesting. I thought I read about that somewhere but had forgotten. I think it survives reboots, but not shutdowns.

So if I set the CPU fan to 710....that is essentially like setting the min speed. Might have to try that. I see where is automatically kick up the exhaust fan to 100rpm higher than the CPU fan.

-Kevin

What hang ups do you have about letting SMCfan run in the background? I'm just curious.

The reading for the "expansion" slot might be for the GPU. Also, is it the internal case ambient temp or the room temp?
 

netnothing

macrumors 68040
Mar 13, 2007
3,806
415
NH
What hang ups do you have about letting SMCfan run in the background? I'm just curious.

The reading for the "expansion" slot might be for the GPU. Also, is it the internal case ambient temp or the room temp?

I have less of a hangup knowing that smcFancontrol 'sets' the min speeds now and can be closed. I thought smcFan was doing some 'black magic' to get fans to spin up.....but now that I know what's going on I feel ok about it.

My machine is up 24/7, so I don't have to worry about it resetting.

I'm playing around with settings now. I've knocked the CPU fan down to 590rpm....this is about 90rpm above the default. There seems to be a sweet spot somewhere around here that will keep everything cool during normal use (I'm a web developer, so no heavy rendering usually).

Again, I have all the slots filled.....4 of them being filled with 2GB DIMMS, so I understand the heat generated is going to be high. I just wish Apple would have programmed the fans to kick up if the temps start to reach 70C+ on the RAM. Even 100rpm or so seems reasonable to me to keep things cooler.

-Kevin
 
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