what is the TJMAX for a Q9450?

I believe 90C to 105C is correct. Just like stock voltages vary from chip to chip so do temperatures. With that said 100C is the most likely temp.
 
The that temperature is simply the maximum temperature the CPU can operate at and remain below it's rated TDP; like drescherjm it will vary from chip to chip a bit.
 
The target Tjmax is 100C. That would be the best number to use.
FreiDOg said:
The that temperature is simply the maximum temperature the CPU can operate at and remain below it's rated TDP; like drescherjm it will vary from chip to chip a bit.
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No, that is not what Tjmax is.
 
I thought I read the TJMAX is more like 85-95.. even though Intel's published TJMAX is 100C, it's not reasonable for all chips or even most.
 
angelicvoices said:
I thought I read the TJMAX is more like 85-95.. even though Intel's published TJMAX is 100C, it's not reasonable for all chips or even most.
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I don't think you're remembering what you read correctly. If the target Tjmax is 100C, the actual Tjmax will be close to that, although it's impossible to know the exact number since there's no way to read it from the CPU. The best number we have to go on is the target Tjmax, which is 100C for this CPU.
hclarkjr said:
95 seems to be the correct number.
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It's 100C for all non-Extreme Edition 45nm Core 2 Quad CPUs.
 
Zero82z said:
I don't think you're remembering what you read correctly. If the target Tjmax is 100C, the actual Tjmax will be close to that, although it's impossible to know the exact number since there's no way to read it from the CPU. The best number we have to go on is the target Tjmax, which is 100C for this CPU.

It's 100C for all non-Extreme Edition 45nm Core 2 Quad CPUs.
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no way, if i set it to that my temps read over 40c which is wrong. my bios reading was 26C so there is no way it is 100
 
hclarkjr said:
no way, if i set it to that my temps read over 40c which is wrong. my bios reading was 26C so there is no way it is 100
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BIOS temp readings are notoriously wrong. And it's not uncommon for a Q series chip to be over 40c idle.
 
hclarkjr said:
no way, if i set it to that my temps read over 40c which is wrong. my bios reading was 26C so there is no way it is 100
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Idle temps are useless with Core 2 CPUs, since the sensors become more inaccurate the farther away from Tjmax the temperature is. You need to be above 50C to really get accurate readings. Check your load temps with a program like IntelBurnTest or OCCT and you'll find that your numbers check out with a Tjmax of 100C.
 
Zero82z said:
Idle temps are useless with Core 2 CPUs, since the sensors become more inaccurate the farther away from Tjmax the temperature is. You need to be above 50C to really get accurate readings. Check your load temps with a program like IntelBurnTest or OCCT and you'll find that your numbers check out with a Tjmax of 100C.
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Indeed, Zero is right here guys. Even over 50C you are never getting a "correct" reading, what matters is the distance to TjMax, the programs like RealTemp Or CoreTemp are guessing what the temperature is based off the distance to TjMax and the "target" TjMax of 100C.
 
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edit:
Found it, this is last word I know of on DTS and Tjmax from Intel (and frankly anyone else would have a very difficult time convincing me they know more about it).
http://intel.wingateweb.com/US08/published/sessions/TMTS001/SF08_TMTS001_100s.pdf

Associated document on revision of Intel "Quiet" technology to control fan speed with DTS etc. etc.
http://intel.wingateweb.com/US08/published/sessions/TMTS003/SF08_TMTS003_100r.pdf
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I too agree that Delta to TjMax is what matters once the machine is verified working properly but keep in mind idle temps/DTS readings are a decent indicator that the HS is installed properly and case airflow is sufficient. But yeah.

Here is all I was ever to find on a public disclosure of TjMax (the associated Power Point slides of the presentation I can no longer find.)

From the Intel Developer Conference summarized at this link.
http://www.anandtech.com/weblog/showpost.aspx?i=478

45nm Desktop Dual-Core Processors
Intel Core 2 Duo processor E8000 and E7000 series - 100°C

45 nm Desktop Quad-Core Processors
Intel Core 2 Quad processor Q9000 and Q8000 series - 100°C
Intel Core 2 Extreme processor QX9650 - 95°C
Intel Core 2 Extreme processor QX9770 - 85°C

If anyone has Intel published information that contradicts this I would love a link.

Keep in mind the data-sheets very specifically says each CPU is factory calibrated with its own individual TjMax so the number above are likely manufacturing goals but it is likely the actual values are within a couple of deg C of target.

TjMax is the the temp/trip point where the CPU sends out a PROCHOT interrupt which the board bios (EIST etc.) uses to spin the CPU fan up to 100% speed no matter what in an attempt to cool the CPU. Several deg C above that (data-sheet for the first mobile CPUs using DTS indicate 10-15C above) the Catastrophic Trip point is reached, "catastrophic" in that the fan apparently has failed - not the CPU, the chip will shut itself down to save itself.

Again if anyone has any Intel docs to the contrary I would like to see them so I have the story straight.

Good article on DTS - bit dated but still the best Intel discussion I can find. Wish I had that IDF power point presentation, it talks about the slew error alluded to in previous post etc.
>>>edit: see links at top. <<<
http://www.intel.com/technology/itj/2006/volume10issue02/vol10_iss02.pdf
(page 109)
 
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