Core 2 Duo temp check please

Tooks · 26 Jun 2007 at 00:05

No, that is not proof I'm afraid. With respect, your trying to backup your argument using what is most likely a flawed temp reading. I'm not sure what's going on with both your temps, but the science behind it is simple.

Think about it for a second. You are using fans to cool the heatsink attached to your CPU. So, you're blowing air already at ambient temp across something that is above ambient temp, your heatsink. You are using forced air convection using air which itself is at ambient temp. What, exactly, is cooling the air down in this simple process? Nothing. The air whether moving or not will be at the same temp.

The wind blowing across your face on a breezy day feels cooler because your skin is evaporating water, giving a cooling effect, which is not happening on your CPU cooler.

Basically, you cannot cool your CPU using air (or water cooling for that matter) below the ambient temp of your room/case.

Try putting a calibrated thermometer in a glass of water in your room, or your case if there is space, and watch what it reads.

Incidentally, what mobos are you running with these temps, and when did you buy your CPU's?

EDIT: Thanks ns400r

Jono8 · 26 Jun 2007 at 00:06

ns400r said:
Not a snowballs chance in Hell of that happening !
You can't transfer heat from a cold object to a hot one.

http://theory.uwinnipeg.ca/mod_tech/node79.html

http://www.ulanet.com/basic_concepts.htm

http://en.wikipedia.org/wiki/Heat

Proof that the sensors are wrong!

Those links prove what i am trying to say. If the heat transfer is effecient enough, the heat from the cpu will transfer into the cold object (the heatsink)

Sean_UK · 26 Jun 2007 at 00:07

Well what ever the relative science, all i can tell you all is when placing my hand on heatsink pipes they not even remotely warm.

Tooks said:
Incidentally, what mobos are you running with these temps, and when did you buy your CPU's?

Asus P5K Delux and CPU new as of today.

ns400r · 26 Jun 2007 at 00:08

Jono8 said:
Those links prove what i am trying to say. If the heat transfer is effecient enough, the heat from the cpu will transfer into the cold object (the heatsink)

Yes but it will NEVER drop below the ambient temperature! And in a real world it will actually still be above ambient.

Tooks · 26 Jun 2007 at 00:09

Jono8 said:
Those links prove what i am trying to say. If the heat transfer is effecient enough, the heat from the cpu will transfer into the cold object (the heatsink)

Yes, which will transfer to where exactly? The ambient air blowing across your heatsink.

The laws of thermodynamics say that your CPU will NOT get colder than your heatsink and your heatsink will NOT get colder than the ambient air blowing across it. Therefore, everything will be at a MINIMUM as warm as the ambient air, and in all likelihood your CPU and Heatsink will be quite a bit warmer.

Jono8 · 26 Jun 2007 at 00:09

Tooks said:
No, that is not proof I'm afraid. With respect, your trying to backup your argument using what is most likely a flawed temp reading. I'm not sure what's going on with both your temps, but the science behind it is simple.

Think about it for a second. You are using fans to cool the heatsink attached to your CPU. So, you're blowing air already at ambient temp across something that is above ambient temp, your heatsink. You are using forced air convection using air which itself is at ambient temp. What, exactly, is cooling the air down in this simple process? Nothing. The air whether moving or not will be at the same temp.

The wind blowing across your face on a breezy day feels cooler because your skin is evaporating water, giving a cooling effect, which is not happening on your CPU cooler.

Basically, you cannot cool your CPU using air (or water cooling for that matter) below the ambient temp of your room/case.

Try putting a calibrated thermometer in a glass of water in your room, or your case if there is space, and watch what it reads.

Incidentally, what mobos are you running with these temps, and when did you buy your CPU's?

EDIT: Thanks ns400r

p35c-dsr3, bought the mobo and cpu a week ago. Was getting 30 degrees idle but since fitting new fans to the infinity and letting the thermal paste settle they have dropped to these temps. I find it hard to believe that every temperature monitor is wrong, in both of our systems.

Jono8 · 26 Jun 2007 at 00:11

Sean_UK said:
Well what ever the relative science, all i can tell you all is when placing my hand on heatsink pipes they not even remotely warm.

Asus P5K Delux and CPU new as of today.

me too, infact they feel pretty cold to touch, like normal metal (cold to touch)

Tooks · 26 Jun 2007 at 00:13

The common theme is that you're both running newish chipsets and new CPU's. I won't pretend to know enough about the chipsets to suggest what might be going on, but the laws of physics (and the information that you yourselves have shared) mean that something isn't quite right.

You say you can't believe all the sensors on your boards are wrong, but how many are we talking about? There is only probably one for the Mobo, and one usually read by Coretemp/TAT within the CPU itself. Maybe Intel have changed something on the newer CPU's that mean traditional temp readers are not working properly, who knows. In time, I'm sure it will shake out.

But, if the ambient temps you guys are telling me are correct, then the reported temps will be wrong.

I would love your temps to be that low, I really would (heck I'd love my temps to be that low!), but I'm genuinely trying to help you understand that they are wrong.

It was a Temp Check thread after all!

Jono8 · 26 Jun 2007 at 00:20

Just checked with speedfan, same temps :confused:

. I get 20-23 idle across the board.

So how the hell can i check my real temperatures. The bios reports the same aswell

i just don't know, maybe my ambient temperature is about 20/22 degrees. I mean its not a particularly hot night.

Tooks · 26 Jun 2007 at 00:26

The answer in the short term is I'm not sure you can unfortunately.

All of the software utilities for temps (asus probe, speedfan, everest, etc etc) use the same sensors on the motherboard as the bios, hence them all saying the same, more or less, allowing for the software doing its own algorithm based adjustments.

The usual exceptions to this are TAT and Coretemp which read from the sensor within the CPU, but it sounds like there could have been a change in the latest build processors that means this no longer works properly. Maybe unlikely though, as my E4400 is a recent build and that seems to be ok on my P5B temp reporting wise.

Or, as the information from the CPU's thermal sensor has to travel through the motherboard to be read by TAT etc (as there is no other physical connection), then it could be that the new mobos you're both running are the issue. That would seem most likely, although obviously I don't know it for a fact, just using my logic.

People far cleverer than me will undoubtedly issue bios updates in due course which will hopefully fix it!

Jono8 · 26 Jun 2007 at 00:29

Tooks said:
The answer in the short term is I'm not sure you can unfortunately.

All of the software utilities for temps (asus probe, speedfan, everest, etc etc) use the same sensors on the motherboard as the bios, hence them all saying the same.

The usual exceptions to this are TAT and Coretemp which read from the sensor within the CPU, but it sounds like there could have been a change in the latest build processors that means this no longer works properly. Maybe unlikely though, as my E4400 is a recent build and that seems to be ok on my P5B temp reporting wise.

Or, as the information from the CPU's thermal sensor has to travel through the motherboard to be read by TAT etc (as there is no other physical connection), then it could be that the new mobos you're both running are the issue. That would seem most likely, although obviously I don't know it for a fact, just using my logic.

People far cleverer than me will undoubtedly issue bios updates in due course which will hopefully fix it!

mayeb, either that or my ambient temperature in the room, is in fact 22 degrees or so :rolleyes:

I have seen it go to like, 23/24 degrees idle on another day and i seem to recall it was a bit hotter that day.

The trouble is the temps don't seem ludicrous or anything. They just could very well be at ambient temps. I mean, they rise accordingly to load e.t.c. going up to 36 or so.

Tooks · 26 Jun 2007 at 00:42

Most people will see their actual CPU temp in the region of 5 to 10c warmer than the ambient air, and with that we mean the air temp within the case, which is made hotter by other components, as that is what's blowing across the cooler.

So, it still seems a little low, but without rushing round to your house with a calibrated thermometer, how would I know?!

As I said earlier, and this would be what I'd do, just stick 10c (to be on the safe side!) on to that temp and use it as the basis for your overclocking adventures!!

I'm sure a bios update will fix it in due course. In the early days of my P5B, there were complaints from users that one of the bios updates had made their CPU temps rise by 15c. It hadn't of course, Asus had just fiddled with the algorithm that tried to calculate the temps to make it a bit more realistic.

Motherboard sensors are notoriously unreliable anyway, and as they are brought in batches of tens of thousands, whole revisions worth of boards can be affected.

EDIT: No need for the rolls eyes face by the way! I'm giving up time to try and help you here!!

Jono8 · 26 Jun 2007 at 00:49

Tooks said:
Most people will see their actual CPU temp in the region of 5 to 10c warmer than the ambient air, and with that we mean the air temp within the case, which is made hotter by other components, as that is what's blowing across the cooler.

So, it still seems a little low, but without rushing round to your house with a calibrated thermometer, how would I know?!

As I said earlier, and this would be what I'd do, just stick 10c (to be on the safe side!) on to that temp and use it as the basis for your overclocking adventures!!

I'm sure a bios update will fix it in due course. In the early days of my P5B, there were complaints from users that one of the bios updates had made their CPU temps rise by 15c. It hadn't of course, Asus had just fiddled with the algorithm that tried to calculate the temps to make it a bit more realistic.

Motherboard sensors are notoriously unreliable anyway, and as they are brought in batches of tens of thousands, whole revisions worth of boards can be affected.

EDIT: No need for the rolls eyes face by the way! I'm giving up time to try and help you here!!

yeh could be. Well even with 10 degrees on top the temps arent near dangerous levels so i'm happy. will have to see whether it is a mistake in the bios and something that can be fixed.

by the way, i didnt mean that smiley in a bad way! i very much appreciate the insight

.

Tooks · 26 Jun 2007 at 00:49

No problem!

Sean_UK · 26 Jun 2007 at 00:50

I should add, this is the 3rd system ive built using this combi of E6600 & Ininity cooler (One for me, two for my younger bro's), and other two systems are showing much the same results (been playing about with other two last 1/2hr)...

Jono8 · 26 Jun 2007 at 00:51

Sean_UK said:
I should add, this is the 3rd system ive built using this combi of E6600 & Ininity cooler (One for me, to for my younger bro's), and other two systems are showing much the same results...

Thats interesting, so were all these systems using different motherboards?

Sean_UK · 26 Jun 2007 at 00:53

One has same board as you, one has Asus 680i.

Jono8 · 26 Jun 2007 at 00:55

Sean_UK said:
One has same board as you, one has Asus 680i.

hm, surely there cant be something wrong with the temp sensor in all of those boards (mine included).

Tooks · 26 Jun 2007 at 00:59

Ok, my last post on this - I need sleep!

The first thing to check is your ambient air case temps with an accurate, calibrated thermometer. Once you know that, and now that you know the laws of thermodynamics, you will be able to tell if the reported temps are accurate or not.

Just make sure you know where you're starting from temps wise. If the reported temps are only a few degrees above ambient case temp, then it's possible they're correct. If they are below the ambient case temp, then they aren't - end of!

The problem is starting with a reliable ambient temp, as you can't rely on the motherboard temp sensors.

PS: If you still insist that your CPU's are below ambient temps, then get onto the dragons den quick, as you've just discovered a way of making free energy without electricity!!

Sean_UK · 26 Jun 2007 at 01:00

All 3 PC's round mine for now, installed them last 2 days and in process of working out everything in BIOS etc and making sure i dont kill anything due to my lack of recent Intel based experiance. I'll get them all overclocked etc and report back my findings here (might be couple of days, lot of work on at mo).

Dont insist anything :confused:

, just stating what i see and not looking for arguement(s)...