Heatsink need re apply?

[vakman]

I have a temperture detector placed on my heatsink, which outputs temps to a gauge on the front of my case, and it reads consistently 5-7C lower than than what mobo monitor and asus probe say my cpu temp is. Is this a normal difference, or is too much heat being lost between the cpu and the heatsink, meaning I should re fit the heat sink, with some new thermal paste?

[Fast420A]

Welcome to the Forums!


You should run the probe between the chip and the heatsink up against the core to get the best temp reading.

[JimmyG]

Fast420A is right, but beware of separating the heatsink from the cpu die. If you temp probe is too thick, it can do that and you end up with a fried cpu.

[Amorphus]

the way they prescribed will get you very close temps to actual, the closer to the CPU, the more accurate.

having the thermal probe in the fin/pin array of the heatsink exposes it to the flowing air, and its taking the temperature of the air flowing past it moreso than the heatsink itself. of course, even if you were taking the temp of the heatsink, because of the heat dissipation, the temperature would be inaccurate also.

[Sonny]

Do not put the probe in between the CPU and the heat sink. What you want to do is to have it contact the side of the die. This way you have the heat sink properly on the die and have good contact for the probe. Good enough for monitoring but nothing to swear by.

[stan03]

some mobos read the temperature high. where exactly is it placed on the heatsink?

[funko]

you want to take the readings close to your cpu core... not teh heatsink... where did you put it?

[vakman]

Thanks for your help. I have also attached a probe to the underside of the cpu. Its supposedly used by the volcano 9 to monitor temperatures, and adjust fan speed, but It worked terribly, fan speeds were way too low! So the best place is to put the probe between the cpu and heatsink, making sure it doesn't compromise contact between the two?

[CrashOveride]

Originally posted by vakman
Thanks for your help. I have also attached a probe to the underside of the cpu. Its supposedly used by the volcano 9 to monitor temperatures, and adjust fan speed, but It worked terribly, fan speeds were way too low! So the best place is to put the probe between the cpu and heatsink, making sure it doesn't compromise contact between the two?

Yes, but if you are only doing this so that your fan will go faster you can just cut off the probe and connect the two wires to make the fun spin at full speed.


Originally posted by stan03
some mobos read the temperature high. where exactly is it placed on the heatsink?

When a mobo reads it high its because it is mis calibrated, or correct.
With a mobo heat sensor it is either in the CPU socket (behind the processor) or using the on-die sensor.

[Sonny]

Originally posted by vakman
Thanks for your help. I have also attached a probe to the underside of the cpu. Its supposedly used by the volcano 9 to monitor temperatures, and adjust fan speed, but It worked terribly, fan speeds were way too low! So the best place is to put the probe between the cpu and heatsink, making sure it doesn't compromise contact between the two?

The only place you can attach the probe on the CPU without compromising the contact between the heat sink & CPU die is on the side of it;

http://www.theforumisdown.com/uploadfiles/0103/cpuprobe.gif

Don't forget to put a little thermal paste on the tip of the probe. What other people do, but will void the warranty, to increase accuracy is to strip some of the plastic from the tip of the probe/ribbon thermistor. This way you have less of a secondary heatpath.

[anvil82]

Originally posted by Sonny

What other people do, but will void the warranty, to increase accuracy is to strip some of the plastic from the tip of the probe/ribbon thermistor. This way you have less of a secondary heatpath.

That voids the cpu warranty, or the thermistor warranty?

[Sonny]

Stripping the plastic on the end of the thermistor voids the warranty on the product that the thermistor came with. Using thermal paste that is not approved by AMD will void your warranty on the CPU too.

[stan03]

Originally posted by CrashOveride

When a mobo reads it high its because it is mis calibrated, or correct.
With a mobo heat sensor it is either in the CPU socket (behind the processor) or using the on-die sensor.

i meant where was he getting his temps from...

@ anvil82 i think the only AMD approved thermal paste is shin etsu (sp?) but someone correct me if im wrong.

[anvil82]

Originally posted by stan03


i meant where was he getting his temps from...

@ anvil82 i think the only AMD approved thermal paste is shin etsu (sp?) but someone correct me if im wrong.

How will they know what you use though? I mean if you need to rma it and you clean it off very well will they actually do some type of test to see if you used the shin etsu?

Hey sonny, is that the Lana Lang chick from smallville? So hot.

[stan03]

thats a good point, i don't really know if they can tell...

[Sonny]

Yes they can tell because microscopic metal particles used will be stuck to the CPU. You should also be aware that Overclockers.com doesnt support bad RMAs.

If you like to use thermal paste that performs well but are within AMD's specification there are a number of alternative pastes that are metal free.

Going back to the topic, I hope you dont make the mistake of sandwiching the thermal probe between the CPU Die & HSF. You will kill the CPU this way.

[vakman]

Thanks very much Sonny, and others!

[eobard]

Originally posted by Sonny
Yes they can tell because microscopic metal particles used will be stuck to the CPU. You should also be aware that Overclockers.com doesnt support bad RMAs.


He's 100% on that. It is frowned upon highly. And his suggestion as to where to place the probe is very good too.

[CrystalMethod]

Originally posted by stan03
thats a good point, i don't really know if they can tell...

For the thermal paste thing. AMD actualy examines the chips they get back. Intel, according to what I gathered at the last conference, doesn't. So feel free to use whatever thermal paste you feel like with the Intels, but be careful with the AMD's. Even though I'm not an AMD person, I'm put out by the fact that they refuse RMA's if you don't use an approved thermal pad.

[stan03]

intel doesn't care if we use thermal paste right? i thought it was only AMD who had the problem with that.

[Soundster]

What do you guys use to hold the temperature probe in place? A piece of tape? if so what kind od tape?

[stan03]

my sfII came with thermal tape.... so i use that