I have a three-year-old PowerMac G5 desktop, the last of the pre-Intel dual-core models. I'm pretty sure you don't need all the specs to answer my question, because the problem is with the fan. Three days ago, it came on and since then, so long as the machine is awake, it never shuts off. It has GOT to be about 120db, ridiculously loud. It used to only come on when the machine locked up, in conjunction with the red light of death lighting up on the front of the tower. But now it has come on with the machine still running and never shuts off. It is like sitting in the room with a jet engine. I suspect this either means my CPU is running hot, or else my thermostat has gone buggy and just THINKS it's running hot.
Suggestions on how to shut it off without disconnecting it?
I had the same problem... It is the logic board... You need to get it replaced. One way you could try to fix it by resetting the board there should be a little black dot behind the front two fans when you open it up. Press and hold for a few seconds... this resets the board to factory settings. The other way is replace the internal battery. and the third is to replace the logic board. $150-200
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
Try running Apple Hardware Test on the machine (it's one of the discs that came with the machine.) Also, if it's freezing by showing the spinning rainbow cursor (beachballing) you may have a failing hard drive. That wouldn't be uncommon for how old the machine is.
Try using the browser Google Chrome, it has flash built in and it is a bit faster. If this doesn't work, you'll have to kill some programs to get more processing power. Press and hold the command key, and then tap tab while still holding command to cycle through your running programs. Let go to stop on one you kill, and then press Command + q to kill it. Do this with as many programs as you can to get better performance, you can always start them up again later. If none of this works, you may need to upgrade your graphics card...sorry.
Thank you for the complete and literate problem statement.
The red light in question will come on and the media bay fan will spin at high speed if the plastic air deflector door is not in place, OR the white sensor label on the lower right tab of the air deflector door is damaged or out of position, OR the air deflector sensor board is faulty.
You can differentiate a bad sensor label from a bad sensor board by doing the following: Remove the air deflector door. Slide a folded piece of paper through the slot in the enclosure where the right tab of the air deflector would normally be inserted. If the red LED goes out (but stays on with the door in place), the sensor label on the door is missing or damaged.
You will also want to check the sensor board cable connection on the logic board (second from right connector located directly below the hard drives).
Subsequent failure for the fans to run does not necessarily indicate a problem, as the fans are temperature-controlled and will not run until heat rises to a certain level. If the fans are not coming on even when the heat is sufficient, you may need to reset the SMU by shutting down the computer, unplugging the AC cord, waiting 15 seconds, and then replugging and restarting the computer.
Try unplugging all Firewire/USB devices. Also, unplug the power cord from the computer. This resets the logic board. If that doesn't isolate the problem, put your Original system CD that came with the computer and hold down the C key. Boot up and run Disk Utility. Run the repair disk and then repair disk permissions. Reboot and try booting your system again.
There are seven diagnostic LEDs near the memory banks of this model: six in a tight line between the edge of the logic board and DIMM bank 1, and the seventh just underneath DIMM bank 1 and slightly more inboard. Please tell me which of these LEDs are on and I will tell you what they mean.
It sounds like you're asking to see if you can add a "core" to your G5. If so, that's not a possibility. Dual core is nice but the G5 is still a powerful machine. If you've maxed out your ram and running a good graphics card and you're still having problems running programs then you should consider an upgrade to a dual core/quad core machine.