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MDD Dual 867MHz CPU Overheating

MDD Dual 867MHz CPU Overheating

I have noted the large number of problems with this particular model and heat issues, but I just received this stripped MDD to do an upgrade on the cheap for my B&W G3 server. In hindsight this might not have been the best unit to upgrade with, but for $72 on ebay (seller was unsure it was dual processor--which may have helped lack of bidding), I figured it was worth it.

After putting RAM to 2GB, putting in an ATI 9200 PCI graphics card, and inserting my HDs from the B&W with updated Tiger installed, everything booted fine with no problems. Dual processors checked out, RAM was fine, and all drives loaded without glitch.

Next go round, after 20-30 minutes it does the sleep/freeze thing everyone has mentioned here and elsewhere. All fans work and have tested with door open and high speed fan directly over heat sink and it still shuts down. Temperature Monitor has it rising above 80c and climbing, which I no longer let go until "closing" to avoid any more damage.

The weird thing about this is that during all of this, the aluminum heat sink remains relatively cool, as if it is not making any contact.

Is it possible it just needs a pad or compound to make contact and dissipate the heat through the sink etc., or does this sound like either a faulty sensor or failing CPU? The compound would be an easy fix (and it sounds logical), but I may just be missing the obvious here. My hope is that the prior owner just did not bother to find out why it did this and cannibalized the unit.

I could take out all the drives, etc. to reduce the heat build up, but I want this to function as a feasible house server that can be left on most of the time + because of the cool heat sink the behavior does not seem to relate to the heat in the housing.

Any and all help will be most welcome.

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Given the price of heatsink compound...

In reply to: MDD Dual 867MHz CPU Overheating

Why wasn't that done?

As to cooling the beast, you may want to entertain fans, etc.

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Fear Factor

In reply to: Given the price of heatsink compound...

I wanted to get some feedback before I started ripping off heat sinks and potentially damaging the processors--since this will be my first dig into a motherboard beyond RAM and PCI cards. I am inclined to do this, but I wanted some confirmation first. From your reply, I assume you feel this is a likely culprit. Does the fact that it still boots etc. prior to overheating hint that the processors are feasibly still good? Thanks in advance.

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Ahh, fear.

In reply to: Fear Factor

I've yet to damage a CPU but I never "rip" off the heatsink. It's always gentle coaxing and kind words of persuasion. If you are still in fear then try the old leave the cover off and point a small fan at the box solution.

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I did . . .

In reply to: Ahh, fear.

and it did nothing to abate the overheating. It is as if the heat sink has no contact point. Do you mean leave the heat sink off entirely? I assume the compound (or pad?) is the route to go next, but my fear is in applying the compound incorrectly. But at this point, I have a 30 minute machine, so I need to do something.

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There are documents on how to apply compound.

In reply to: I did . . .

The method is exactly the same for every situation I've encountered. Type APPLYING HEATSINK COMPOUND GUIDE at google and enjoy.

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Paste Did the Trick

In reply to: There are documents on how to apply compound.

I bit the bullet, went to Radio Shack and got Arctic Silver 5 compound, cleaned off the heat sink and processors with a credit card and alcohol as suggested on their site, screwed everything down, kept the door open with a fan pointed right at the heat sink, turned on and prayed.

With the door open and fan on, I am maintaining a 50.5-51.4C temp. When I close up and let the original (and annoyingly erratic) fan do the work, it maintains between 59.5 to 60.5C. This suggests I need a better fan, but I guess the old paste was just preventing any heat from conducting through to the sink.

Thanks for building up my confidence to actually "touch" the processor. Hopefully I am not too fearless now and avoid cracking open my laptop Wink

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Shopping for fans.

In reply to: Paste Did the Trick

If I remember the fans are standard size and voltage but I can't guarantee that. I find fans on

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MDD Dual 867MHz CPU Overheating

In reply to: MDD Dual 867MHz CPU Overheating

With the addition of the ATI 9200 PCI graphics card, you need to upgrade your Power supply to a 300 watt unit. That will solve the problems of the overheating.

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