Xeon's and Heat

[dringdahl]

Anyone know if a Xeon throttles down automatically when it is overheating???

Testing a couple of Dual Xeon 3.06 boxes, and they seem to have slowed down after a couple hours. This is just an observation, not a scientific test.

Thanks

 

[Wolfsraider]

google showed this

While all Intel processors since the Pentium Pro have internal die temperature sensor diodes, new circuitry has been added in the Pentium 4 and Pentium 4 Xeon processors permiting automatic control of thermal dissipation. When the temperature sensed by a second diode situated in the hottest region of the die reaches a factory defined threshold, the internal clock is automatically stopped until the temperature drops by about one degree celsius. On-off reaction times may be as short as a few microseconds, so that despite high rates of temperature buildup of 30-50 degrees C/sec, the regulator keeps dissipations at or below the Thermal Design Point.

Evidentally, if the Thermal Monitor system is enabled, the most power the CPU can be made to dissipate will be approximately the Thermal Design Power, and Intel operational specifications for the Pentium 4 require that the Thermal Monitor throttling be enabled, either in BIOS or via software driver. However, like the Athlon XP, the CPU can be operated at higher dissipations if the Thermal Monitor is left disabled.

When operated at the same clock rate and core voltage, AMD processors for a particular stepping have similar thermal ratings, but Pentium 4 processors may have very different ratings even though they have the same stepping. As an example, data for Pentium 4 stepping B0 are plotted below:

seems that they do...and being the flagship,it wouldn't make a lot of sense for them not to.

mike

 

[InlineFive]

What kind of case do you have and could you post cooling specifications?

 

[dringdahl]

They are 1u boxes from appro. Getting ready to setup a cluster.

When the CPU throttles down, you cant tell from the cpu utilization it would assume. Is that correct?

TIA

 

[InlineFive]

Hmm, they would throttle down if they were getting too hot. See if any of the blowers aren't working. And otherwise I would call Appro about it.

 

[BadThad]

As I recall the throttling temp is VERY high on P4's....somewhere around 95°C. I seriously doubt you're getting that hot.

 

[Unforgiven]

here is an interesting article with some graphs. linkage
it does appear that in order for throttling to kick in you would have to do something drastic, such as unplugging the heatsink, to have the temp spike to above 85 C and for throttling to take over. its not a comparison with the xeon processor but its the rest of the P4 line and i found it quite informative.

 

[Zbox]

I've had the throttling kick in before on four xeon machines - three dual, and one quad. Each were in a 2u box. Some schmuck turned my air conditioning off to my server room over the weekend and I was using these things as crunchers. I came in on monday to find the things crawling and the noise level from the "smart" fans was equal to standing .25mm behind a fully throttled jet engine. FIRED~~~!