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Fourth Horseman · Dec 12, 2006, 12:55 AM

Tonight I dropped a 2 GHz Core 2 Duo T7200 processor into my Mac Mini (previously 1.5 GHz Core Solo). The upgrade was rather tricky, as I've never had a Mini apart before. Working in these small computers is entirely different from a normal sized desktop machine.

After much careful disassembly/reassembly the machine booted right up. My only concern is processor temperature. Under light load (web browsing, etc.) the CPU runs from 55C to 60C. No worries there, but once I get BOINC fired up that temp shoots up to 90C! The specs say the CPU is safe up to 100C and will go into thermal protection at 125C, so perhaps I have nothing to worry about, but 90C seems a bit high to me. I used a very thin layer of Artic Silver as I do with all my CPUs and everything seemed ok.

Do you guys think I have anything to fear from 90C operating temperatures?

Scotttheking · Dec 12, 2006, 01:09 AM

That is disturbingly hot.

--Scott

Fourth Horseman · Dec 12, 2006, 01:27 AM

Yeah, it's got me a little spooked. I think I might pull the machine apart and make sure the heatsink didn't pop one of it's anchors loose while I was reassembling everything. That's the only thing I can think of that would be leading to these kinds of temperatures.

SciFrog · 05:40 PM

My two iBooks (one C2D, the other CD) can reach 86-88 when not on a flat surface. On a desk, they will settle down to 78-80...

Fourth Horseman · Dec 12, 2006, 09:22 AM

That seems much more reasonable. I'm guessing my heat sink got messed up when I was trying to reassemble the machine. I'll open it up tonight and check. Thanks for the feedback on the temps.

zombie67 · Dec 12, 2006, 11:19 AM

Originally Posted by Scotttheking

That is disturbingly hot.

--Scott

Not really. More Core Duo (2.16) in my 17" MBP hovers around 88-89 C. Completely stock.

Fourth Horseman · Dec 12, 2006, 01:54 PM

Originally Posted by zombie67

Not really. More Core Duo (2.16) in my 17" MBP hovers around 88-89 C. Completely stock.

Interesting. Perhaps I have nothing to worry about then. I'm still going to check my heat sink, but it sounds like maybe these Core Duo and Core2 Duo chips just run hot. Thanks for the info on your CPU's temps.

beadman · Dec 12, 2006, 03:21 PM

My MBP 2.16 runs SETI 24/7 - Processor 1 is normally at 89-90C with processor 2 at 85-86C. I keep the laptop on my wooden desk at work, but have it elevated on a couple of flat sticks to let the air circulate beneath it a bit. Fans operate quietly (not full speed).

beadman

Fourth Horseman · 10:51 PM

Thanks guys, you've eased my fears. I'll power my little Mac Mini back up without fears of China syndrome.

EDIT: I pulled my Mac Mini apart again and my heat sink was in place as it should be. So it looks like the Core2 Duo just runs warm. I put it all back together and have it cranking away on S@H and R@H now. I'll let you guys know if it starts showing any signs of problems due to the heat.

In the mean time, this is a happy sight.

Tomchu · Dec 12, 2006, 11:38 PM

You do have to clean both the processor and heatsink with rubbing alcohol to remove *any* old thermal interface material, and then you have to apply fresh stuff.

amru · Dec 13, 2006, 01:34 AM

its just a plug and play type of mod? meaning just take the old one out and drop the new one in? and nothing else

Scotttheking · Dec 13, 2006, 01:37 AM

Originally Posted by amru

its just a plug and play type of mod? meaning just take the old one out and drop the new one in? and nothing else

Yes.

Tomchu · Dec 13, 2006, 02:41 AM

Along with proper cleaning of the thermal surfaces and application of new thermal interface material ...

A quick drop-in job is what gets you temperatures of 90C. :-)

Scotttheking · Dec 13, 2006, 02:48 AM

Intel's site says thermal spec is 100C, which is very scary to me. But, ok...

zombie67 · Dec 13, 2006, 03:02 AM

Originally Posted by Scotttheking

Intel's site says thermal spec is 100C, which is very scary to me. But, ok...

We've been though this. 100c is okay. Run BOINC, and let credits do the talking. If you had a faulty HS connection, then it would have burned up within minutes.

Fourth Horseman · Dec 13, 2006, 09:21 AM

Originally Posted by Tomchu

Along with proper cleaning of the thermal surfaces and application of new thermal interface material ...

A quick drop-in job is what gets you temperatures of 90C. :-)

Yup, that's been done. It was completely cleaned and a new thin application of Arctic Silver was used. As Zombie says, it appears to be just the way these Core processors run.

Tomchu · Dec 13, 2006, 03:19 PM

Strange. I deal with Core 2 Duos at work and none of them ever run that hot -- then again it's with the stock Intel heatsinks, which are more powerful cooling devices than the quiet, miniature system that the Mini has.

Fourth Horseman · Dec 13, 2006, 11:32 PM

Originally Posted by Tomchu

Strange. I deal with Core 2 Duos at work and none of them ever run that hot -- then again it's with the stock Intel heatsinks, which are more powerful cooling devices than the quiet, miniature system that the Mini has.

I definitely think that's a factor. It would explain why people with notebook systems are seeing similar temps. I think the Mini's heatsink and fan just aren't up to the task of a CPU pushed to full throttle like this. I could always mount the whole thing in a bigger PC case with a better heat sink and multiple fans, but I'd really hate to give up the small, stylish enclosure. Still, the temperature is steady at 89C - 90C and I've not seen any instability or odd behavior so far. It seems stable at these temperatures.

SciFrog · Dec 13, 2006, 11:47 PM

Using Core Duo Temp program, it looks like my 2Ghz Core Duo tops at 1.83Ghz and 76c running Folding. Any suggestions?

beadman · Dec 14, 2006, 09:15 AM

Originally Posted by SciFrog

Using Core Duo Temp program, it looks like my 2Ghz Core Duo tops at 1.83Ghz and 76c running Folding. Any suggestions?

Go into your Systems Preferences/Energy Saver and set the performance to Highest Performance - I believe the default is either Normal or Better Energy Savings. I have my MBP set to Custom, with Computer to Sleep: Never, and Display to Sleep: 3 minutes, and Put Hard Disk to Sleep When Possible (I also have my BOINC prefs set to write to disk at most every 900 seconds). No guarantees, but my RAC went up when I did this on the MBP.

beadman