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sleddog
12-02-2000, 05:48 PM
I realize that overclocking isn't recommended for all, but I'm being careful http://www.PCGuide.com/ubb/smile.gif An experiment of sorts. What I'm looking for is some sort of baseline data for CPU temperature... for example what is safe, what is theatening destruction. I'm working with a Celeron 600 CPU. Without going into details immediately, when clocked at 600 I see CPU temps in the 70-85 degree Celsius range (with a heavy CPU load). When overclocked (up to 800) I see temps that range up to 98 Celsius). Is there a danger point? Is there a temp that I should *not* let it exceed? My NT4 workstation keeps plugging along w/o error or crash. (And yes I'm working on improved cooling.)

THanks for any comment.

Paleo Pete
12-03-2000, 05:25 AM
Sometimes I hate search engines!! Half an hour and I still can't find a thing....

Anyway, I'll bypass my usual lecture since you seem to be aware of the risks and are trying to be cautious. About all I can find so far is This Page (http://overclockers.cssftware.com/cpudb/index.cfm) at overclockers.com where you can select your CPU and see a list of the results of other peoples' efforts, often including the temps they got with different setups.

A general rule is if you can't hold your finger on the CPU for 10 seconds, it's too hot. Be careful, you don't want to become all that friendly with the current running through the circuitry...

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Soon as I come up with all the answers...they change the questions!!

Computer Information Links (http://www.geocities.com/paleopete/)

sleddog
12-03-2000, 07:44 AM
Thanks Pete.

Yes I am being cautious.

I've been through the overclockers.com site extensively without much luck. To start with they don't list the Celeron 600 (only a Celeron II 600, which I think is a different beast).

I've never understood the 10-second rule. The CPU has a heatsink and fan on top, making it difficult to put my finger on it http://www.PCGuide.com/ubb/smile.gif The edge of the CPU that I *can* touch feels quite cool. And needless to say I'm not going to run it with the heatsink/fan removed.

Does 'Palaeo' relate somehow to archaeology? That used to be my trade.

sleddog
12-03-2000, 10:26 AM
OK, I've found these specs at Intel support site: http://support.intel.com/support/processors/sspec/icp.htm

For the Celeron 600 it gives the "Thermal Spec" as 90 degrees C.

So what does "Thermal Spec" mean? A safe maximum operating temperature?

Paleo Pete
12-04-2000, 05:31 AM
I never thought to check Intel's site...

Yes, Paleo refers to the Archaeology/Paleontology fields, an explanation of how it came about can be found in This Topic (http://www.pcguide.com/ubb/Forum10/HTML/000002.html), along with some really cool stories from many of the good folks on this forum explaining how they became computer nutz.

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Soon as I come up with all the answers...they change the questions!!

Computer Information Links (http://www.geocities.com/paleopete/)

sleddog
12-04-2000, 01:25 PM
Well, here's some info for the record.

I undid overclocking and ran the CPU at its stock 600. Running SETI which utilizes 100% CPU, CPU temperature climbed into the high 70's C. I've read a lot of overclocking advice which referred to temps in the 30's and 40's -- 78 C seems extremely high for a stock CPU!

So I removed the heatsink and fan for a look. I purchased the CPU and m/b by mail -- the shop installed the CPU before send it. Great I thought when I saw this, saves me the trouble. But I found today that the shop had installed the heatsink backwards. On the bottom of the heatsink there's a sticky tab that increases thermal conductivity. Because the heatsink was on backwards only 1/2 of the raised heat-dissipation area of the Celeron CPU was making contact with this tab.

I reversed the heatsink and rebooted. Now running at 600, SETI puts the CPU temp to about 38-40 C, some 40 degrees cooler than before. This could be a lot better I think with some heatsink compound. The sticky tab on the heatsink is now slightly damaged and not making perfect contact with the CPU -- but I don't have any at hand and the nearest comp. store is 1,000 km away http://www.PCGuide.com/ubb/frown.gif

Overclocking? I'm now running at 854 Mhz, stable, and while typing this message the CPU temperature have fallen to 16 C http://www.PCGuide.com/ubb/smile.gif (SETI now raises it to a maximum of 42 C).

Paleo Pete
12-04-2000, 02:06 PM
Upside down heat sink??? I'm amazed it didn't fry the thing!

I don't know if Radio Shack even exists in Canada, but they have heat sink compound, which is 10 times better than the heat tape that was put on your CPU. If you can't find any let me know, and email me an address, I have a tube here and can put enough in a zip lock bag to do the trick and mail it your way. Should only cost a 33 stamp. I bet that's cheaper than a 1000 mile drive! Or whatever that translates to in English...Check around, you might get lucky and find some in an electonics shop.

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Soon as I come up with all the answers...they change the questions!!

Computer Information Links (http://www.geocities.com/paleopete/)

sleddog
12-04-2000, 07:52 PM
Not upside down, but reversed 180 degrees. The heatsink isn't symmetrical and the cooling tab thing isn't in the centre.

Thanks for the offer of the heat sink compound. I'll take you up on it if my wife can't get it at Radio Shack this week during her visit to the big city.

sleddog
12-06-2000, 06:34 AM
For the record, anyone interested in cooling issues might have a look here: http://www.heatsink-guide.com

kenja
01-01-2001, 07:53 AM
Thanks to sleddog's link I now know what a peltier cooler is. Don't think I need one, though... http://www.PCGuide.com/ubb/smile.gif