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Discussion on Article:
An Extreme Tower: Tuniq Tower 120 Extreme Cooler Review

Started by: Bo_Fox | Date 11/30/09 08:18:10 PM
Comments: 12 | Last Comment:  12/11/09 03:11:49 PM

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1. 
A blissful article!!

I'm surprised that the Tuniq Tower 120 Extreme is still behind the IFX-14 by some amount. At first, it looked like as if the direct-touch heatpipes (5 of them, with 3 of them being 8mm) and a similar structure as the IFX-14 would have enabled it to perform just as good. Well, this test is a bit difficult because the base of the IFX-14 was "evened-out". I also lapped my IFX-14 and it yielded like 6-7 degrees cooler.

I'm guessing that it has a bit lower heatsink surface area than the IFX-14, and roughly equal to Thor's Hammer?
0 0 [Posted by: Bo_Fox  | Date: 11/30/09 08:18:10 PM]
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2. 
Your screen shot on page 5 shows that you are likely using the wrong TJMax value in RealTemp. Most of the C0 Stepping Core i7-920 CPUs thta I have seen have a TJMax = 100C, not 95C.

If you click on the Defaults button in the RealTemp Settings window it should read the correct value directly from the CPU. Core Temp also uses the correct TJMax value. Some other software does not.

Here's RealTemp 3.49 with ATI GPU temperatures as well.

http://www.fileden.com/fi.../1794507/RealTempBeta.zip
0 0 [Posted by: unclewebb  | Date: 11/30/09 09:49:55 PM]
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Your screen shot on page 5 shows that you are likely using the wrong TJMax value in RealTemp. Most of the C0 Stepping Core i7-920 CPUs thta I have seen have a TJMax = 100C, not 95C.

You are not right, see the documentation:
http://processorfinder.in.../details.aspx?sSpec=SLBCH
0 0 [Posted by: Jordan  | Date: 12/01/09 12:45:22 PM]
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Jordan, you don't know what you're talking about.

TJMax is written into each core of every Core i7 CPU. The information you posted has nothing to do with TJMax.

http://img692.imageshack.us/img692/931/tjmax.png

Intel's name for TJMax is Temperature Target. Starting with the Core i7, this information can be read directly from the CPU.

The link you posted shows the maximum Tcase temperature which has nothing to do with TJMax.
0 0 [Posted by: unclewebb  | Date: 12/01/09 01:37:39 PM]
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The link you posted shows the maximum Tcase temperature which has nothing to do with TJMax.

I say "see the documentation", not the spec's of CPU.
http://www.intel.com/design/corei7/documentation.htm
0 0 [Posted by: Jordan  | Date: 12/02/09 03:33:26 AM]
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Yes Jordan, I've read that documentation. That's why I posted the relevant information on how to read TJMax from a Core i7 CPU. You can use any program that lets you read model specific registers from Intel CPUs. My MSR Tool is capable of this.

http://www.fileden.com/files/2008/3/3/1794507/MSR.zip

Start the MSR Tool, enter 0x1A2 into the MSR Number box at the bottom and then click on Read MSR. If you actually have a Core i7-920 C0 stepping then you are very likely going to see the hexadecimal number 64 in bits [23..16] of that register. 64 hexadecimal is equivalent to 100 decimal and that is the TJMax of your processor.

If you have an i7-920 then post a screen shot of that register.
0 0 [Posted by: unclewebb  | Date: 12/02/09 09:05:32 AM]
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Just one question
If you are right, why the throttling started when the temperature (from RealTemp) reaches 95 degrees of Celsius?
0 0 [Posted by: Jordan  | Date: 12/02/09 12:17:42 PM]
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There are two types of throttling. First there is turbo throttling where a Core i7-920 will start to drop the +1 turbo boost and it will cycle the multiplier from 21 to 20. This can happen hundreds of times a second. This happens on the Asus P6T based boards when significantly overclocking them and the core temperature reaches about 80C.

For thermal throttling, this will happen close to the official TJMax temperature. On Core 2 CPUs, it tends to happen about 2C or 3C before the official TJMax number. When the Distance to TJMax shows 2 or 3 in RealTemp, the thermal throttling bit will be triggered and in the Thermal Status area of RealTemp, it will change from OK to LOG which shows that at least one thermal throttling episode has been logged.

The actual core temperature can change very rapidly when there is a problem with a heatsink or what have you. RealTemp samples the CPU once per second so it's possible to trigger thermal throttling without RealTemp reporting 100C. When the multiplier cycles down to the default of 12, the temperature can drop back down instantly as well. There is a lot of energy flowing through a very small device so rapid temperature changes do occur.

I wish I had a few more details from Intel but I don't. The rated TJMax is contained in MSR 0x1A2. The Core i7 CPUs I've seen tend to trigger the thermal throttling bit within 1 degree of the number in this register.

If the temperature is changing rapidly, RealTemp might report 95C even though the temperature quickly went beyond that temperature before dropping back. To test you would need to increase the core temperature in a very slow and controlled manner.

If you use the TJMax that is written into the CPU, your reported core temperatures for core 0 will be extremely accurate from idle to TJMax. The sensors in the Core i7-920 are excellent. They don't have the problems that the previous 45nm Core 2 sensors had. It's my opinion that Intel sets the TJMax 5C higher on core 3. If Core 0 is set to 100C in the MSR then in almost every case, core 3 will have an actual TJMax close to 105C regardless of what the register says for that core. The two center cores might have a slightly different TJMax but they tend to be fairly close to core 0. I believe Intel does this deliberately to better control thermal throttling so all 4 cores don't reach the thermal throttling point at the exact same time. Just a theory I have and there is no documentation from Intel to support this idea. If you see enough screen shots of Prime95 running Small FFTs then you might agree with this conclusion.
0 0 [Posted by: unclewebb  | Date: 12/02/09 03:12:19 PM]
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3. 
Jordan for Christ's sake you speak with Kevin, RealTemp author.
I have a feeling that he knows damn well Intel docs.
0 0 [Posted by: burebista  | Date: 12/02/09 09:32:54 AM]
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4. 
Awesome read, thanks, unclewebb!

It was a honor speaking to you on [H]Forums and on XS a while ago!

Once again, I really made a good use out of your RealTemp utilities. You're the man!
0 0 [Posted by: Bo_Fox  | Date: 12/03/09 02:06:07 AM]
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You're welcome Bo_Fox. My tools are based on all the feedback I've received from those two user communities. I've put a lot of work into my tools and believe that they do a good job of telling it like it is. With Core i7, I definitely wouldn't change TJMax without a good reason.
0 0 [Posted by: unclewebb  | Date: 12/03/09 08:50:50 AM]
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5. 
might be nice to see the original tuniq tower up against the new tuniq tower for a comparison
0 0 [Posted by: Athlonite  | Date: 12/11/09 03:11:49 PM]
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