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webphotogrl · Jun 20, 2008, 12:28 AM

Hi all! Hope you can help me out...

I have an iMac Graphite SE DV 600mHz. My baby, have had forever!... My problem is that it shuts down intermittently
by itself. It seems that the more I'm doing, the faster it will shut down. I've had it on and not doing anything all night long, but as soon as I start playing, it shuts down. Any thoughts on what it can be? Are there any upgrades for this model?
Any help would be appreciated SO much! Thanks!

moonmonkey · Jun 22, 2008, 01:09 AM

Its most likely overheating, check all the vents are clear of dust.

webphotogrl · Jun 22, 2008, 05:17 AM

All of the vents are free of dust...

Sherman Homan · Jun 22, 2008, 08:01 AM

I think moonmonkey is right, that model has no fan and there may be a blanket of dust inside. Try installing iStat or Temperature Monitor, it should give you info about how hot things are getting on the motherboard.
Just to complicate things, what Mac OS are you running on that? Make sure you check what version of those two will run on your iMac.

webphotogrl · Jun 24, 2008, 04:11 AM

Thank you both for your suggestions!
Operating System: OS 10.3.9
As far as the overheating goes... if I find out that it is getting too hot, then what now? There is no space for a fan...right?

Sherman Homan · Jun 24, 2008, 06:25 AM

Getting a fan in there is not easy, it can be done, but those models are designed to be compact, which means no room. I would run Temperature Monitor to see if it really is hot in there. Open up that case and go at it carefully with a can of compressed air. If there is a problem it will be with the processor's heat sensor.

P · Jun 24, 2008, 09:20 AM

That model has almost no temperature sensors - I have a similar one. There is one in the CPU itself, but that one is only accurate to about 4 degrees C/8 degrees F - don't think that Temperature Monitor even reads that one. You can tell if the CPU is burning up or if it's fine, but nothing more. I have put a manual thermometer in one like that once (one of those that has two digital displays, in and out - I stuck the "out" sensor inside the shell) to get better data.

There is no good way to get a fan in there. You can steal some power from the HD or DVD, but there is no good place to put it. Ideally, you want to have cool air pushing onto the overheating part, but in this case the air is supposed to exit upwards. You'd interfere with the natural airflow. Of course, you can make sure that there is nothing hot on top of the case (like a desk lamp), that the ambient temperature isn't too high, that the iMac isn't standing in bright sunlight but beyond that...

Note that the intake vents are underneath along the sides - that's where the dust would sit. The visible vent at the top is the outflow. It may also sit in the EM screen (the mesh just inside the cover). Vacuuming is good. Best is if you can complement with some compressed air in a can.

I think that what is happening is that the powersupply (PSU) is straining when you start gaming, and that it is overheating because of that. This may be because there is less airflow, but also (and more likely) because the PSU is worn. The PSU is one of the parts that does wear out, eventually. It is specific to that model (actually part of the analog board and not a separate unit) and cannot be replaced. While you might theoretically reduce strain by disconnecting stuff, I wouldn't bother. If you can't improve the airflow, buy a new one before it dies completely. Refurb Mac minis (if you have access to a separate monitor) and Macbooks (if you don't) make good replacements.

FWIW, mine died a week ago. I got it going again, but it's just a question of time. It's certainly cooler in Sweden than in Arizona, but then mine is two years older as well. Old computers die eventually, and that big old CRT isn't helping.