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"Acceptable" CPU Temps?

S

ScanDisk

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Niagara Falls, Canada Eh?
I have owned a Thinkpad T42 for about the past two months, and it's great. Only complaint I have about it, is that the fan is rather loud, and I found out that it's normal for Thinkpad's of it's age and series to have a lot of fan noise, because the BIOS fan controller makes the fan go much faster than it needs to be most times.

Because of this someone made a program called TP Fan Control, where you can control fan speed from Windows (XP in my case).

I just tried using it, and while playing Old School Runesape (which is the main reason I bought the T42) if I set it to use the BIOS controller the noise sounds as usual, if I use the "smart" option, it sounds the same as with the BIOS option, and the speed is almost exactly the same too (rpm).

However it does also let you enter fixed speeds from 0-7 (0 being fan off, 7 being almost as fast as it can go, and then there's "64" which is truly as fast it can go).

When I have it at 3, the amount of noise sounds the same, but when I turn it down to 2, it is near silent.

It also tells you the CPU temp, and with a fixed speed of "2" I am not seeing higher than 78c, though with BIOS I am seeing 73-75c.

A friend of mine says that Ideal CPU temp is 73c or less, but up to 75c is fine. However my desktop which is running an i7-4790k 4ghz, is usually in the low-mid 80's, and I once saw it under a stress test get to 88c, and it's worked no problem for well over a year since I installed it.

From what I understand if it's running a bit above 75c then, it will still work, but just not last as long as if it was lower.

So I take it that as long as it's not going much above 80c, it's not ideal but would still be "acceptable"?

I mean I've heard that sometimes some CPUs in macs get up to 90, or even 100c.

Of course I don't know much about temps, which is why I am asking.
 
Max on a Pentium M 725 is 100C. If the fan is making noise I suggest you open the case and clean out the heatsink from dust and lube the fan while you are at it.
 
Unknown_K said:
Max on a Pentium M 725 is 100C. If the fan is making noise I suggest you open the case and clean out the heatsink from dust and lube the fan while you are at it.
Click to expand...

I upgraded it to a Pentium M 755 (2.0Ghz) and 2GB RAM (Really 1.5GB, because it seems one of the ram modules I ordered was DOA though I do have a replacement coming in). Of course in order to do that I had to remove the heatsink/fan assembly as well and it did not look dusty at all, in fact all it looked like all it needed was the old thermal paste cleaned off (which of course I did). Also from the looks of it, it's like the fan is inside the heatsink, and not an independent component, so I am not sure of how to lube the fan, or if it is even possible. I guess I will have to do some further research, and I will be able to take another look soon enough, when the replacement RAM gets in as well.

Also, from what I have seen researching the issue, apparently having a lot of fan noise is common for these, which is why the utility I mentioned was created, so I am not quite sure if there even is anything "wrong" per say.

I used Arctic Silver 5 Thermal Paste because I still have most of a tube of it left, after installing the 4790k in my desktop, and I figured if it can adequately cool a more modern i7 processor, it should surely be able to cool any Pentium M no problem. Seeing how I am getting below 80c temperatures with the fan at a low speed, it appears I was right about that at least.
 
Best thing to do with a Pentium M is run Speedswitch XP or Crystal CPUID's multiplier management. Normal voltage, 400FSB models can officially throttle to 600MHz and .956V. Cooling requirements go way down. Unless you're running the CPU load at 100% all the time for some reason.

I'd freak if my CPU temp went above 70C. I know they can go higher than that without actually melting, but it's good to have a fat safety margin, especially considering all the hardware I've seen with plainly inadequate OEM cooling...
 
I get worried if it goes over 50C. Last week I started refurbishing my i7-2600 which had recently started crashing and rebooting by itself, or sometimes refusing to start, with error beeps.

Removal of the 2 extra hard drives fixed the instabilities (maybe the power supply can't handle it any more?). Then I pulled apart the heatsink / fan assembly and cleaned the dust out of it. I noticed there was barely any heatsink compound so I cleaned off the little that was there and put some new silicon compound in.

After that, it seems to be working well although I haven't tried stressing it out yet. The normal temperature is so low (27C) that sometimes the fan switches off, as it isn't needed.
 
My CPUs run from the low 60s to close to 100.

Even with new paste / clean heat sinks / clean fans. Plus with elevation. Especially extreme edition CPUs get hot. One W520 has a 2960XM and one W510 a 920XM. But even a W520 with 2860QM get's hot. Especially when I have stuff open in Chrome and run Age of Empires II HD with the LUDIKRIS map size and > 250 population. The 2860QM hypothetically should perform almost as good as the 2960XM as it is a 45W CPU instead of 55W with far less heat dissipation (far less likely to throttle). I have a W500 with T9600 and integrated GPU (discrete GPU is broken) that keeps nice and cold. I am looking into replacing the MOBO on that W500 to run discrete graphics and am also considering a X9100 (really hot) or T9900 (should be cooler).

http://cpuboss.com/cpus/Intel-Core-i7-2960XM-vs-Intel-Core-i7-2860QM

Interesting how much the top QM performance jumped relative to XM from 1st to 2nd generation. The 840QM is a lot slower than the 920XM.
http://cpuboss.com/cpus/Intel-Core-i7-920XM-vs-Intel-Core-i7-840QM

W520s have separate FRUs for OEM built in fans for XM CPUs by the way.

None of my systems are overclocked.

I have one W510 with a 720QM that I got for $100 in NC in 2018 that needed new paste: it would throttle nonstop: turned out it was clogged with dust and there was no paste left.

I experimented with notebook fan cooling pads: does not make a discernible difference for the ThinkPads I own. A few weeks ago I experimented with vacuums (USB powered) to speed up hot air removal from ThinkPads: no difference either.
 
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Heh, all of this fancy silver goo for heatsinks isn't for me. I use a dab of Permatex aluminum anti-seize compound. I tried the spendy stuff and couldn't discern any significant difference in temperature. There's also a copper-based anti-seize paste as well. Either vastly cheaper than the boutique compounds--and you can use them on the bolts holding your engine's heads.

Lest you think that I'm making stuff up, consider Dan's data that seems to show that toothpaste or Vegemite works just as well...
 
The problem you have with the different heat sink compounds are most work well when new but dry out when they get old and that left over powder does not conduct heat as well. All you need is enough material to fill in any gaps between the CPU and heatsink, NOT enough to make a second layer between the two. So pretty much anything conducts heat better then an air pocket.

I buy cheap HS compound on ebay made in China and it works good enough. They come with different names and colors but most are about the same, I prefer white.

While laptop CPUs are low wattage, the heatsink and fan are total shit (they have to fit in a very tiny space) so even a little dust or a slower spinning fan will cause problems. Pretty much every laptop I get in for the collection needs new heatsink compound and a cleaning. Even if the outside looks clean enough you just need a little bit of dust to clog up the outlet holes to cause over heating. You never know until you take the fan out and look at the copper vents to see if they are clogged. They also use an aluminum foil tape to keep air from leaking around the heatsink and that might need replaced. Same goes for gamer video card heatsink and fans.
 
Notebooks have their uses. Sales people, engineer who work outside of the office etc. I don't compute much these days on the move so my laptops pretty much stay in the house not being used much as I work on my main system in my room or use the server in the basement lab.

Also newer laptops can get pretty toasty so using one in your lap is not the best idea.
 
Just out of curiosity, I am now running Prime95 on the T42 (cpu stress test), it's been running for 15 minutes so far, and the CPU temperature is being reported at 73c right now. This letting the BIOS control the fan speed though, in a while I will try it with a fixed speed of "2" through the TP fan control program and see what happens.

Like I mentioned before, in a day or two I should have a reason to go back inside the laptop, and should be able to get a chance to clean out the fan and heat sink more thoroughly as well, although it looks surface level clean already.

Edit:

I just stopped running it, so in total it was running for about an hour, and it only got up to 78c, and just a couple minutes are I stopped it, it went down to 60c, and it is now saying 54c. So I guess that 78c after an hour of unrealistic stress is not bad.
 
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Chuck(G) said:
Either vastly cheaper than the boutique compounds--and you can use them on the bolts holding your engine's heads.
Click to expand...

If you want blown head gaskets lol. Anti-seize is not for head bolts because it interferes with the torque on the bolts.

Chuck(G) said:
A thin coating of silicone o-ring grease would probably work as well as the exotic stuff, I'm thinking. And a heckuva lot less expensive.
Click to expand...

It'll make your CPU go thermonuclear. I've tried lithium grease and silicone grease because I ran out of thermal compound one time and the CPU idled at 80C.

Best to use cheap white thermal paste if you don't want to pay much. I would not recommend using anti-seize because it's conductive. If the stuff gets outside of the CPU die (and it will), there's the very real risk of it shorting something out.
 
Aluminum anti-seize is not conductive--I've measured it with my megger. Any aluminum particles are covered in a layer of non-conductive aluminum oxide. The oil carrier itself is insulating as well.

Conventional white thermal compound is a silicone grease with a zinc-oxide filler. It's not at all clear that the ZnO contributes much to the equation. Indeed, if this were the case, you'd be as well off using zinc oxide sunscreen as a thermal paste.
 
Somewhat related: a ZR30w I acquired recently shuts down intermittently and gets very hot. With the casing of it appears to be doing much better so far. Curious what could result excessive heat buildup on a 30" IPS panel.
 
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