PM G5 mod w/ more fans?

Discussion in 'PowerPC Macs' started by WalnutSpice, Jul 14, 2016.

  1. WalnutSpice Suspended

    WalnutSpice

    Joined:
    Jun 21, 2015
    Location:
    Canton, Oh
    #1
    Been using my G5 for my work computer at home. Putting some upgrades into it (Got a nice new GPU, upping from 3 to 4GB RAM and gonna get a 1TB WD Blue 7200RPM upping from a 500GB 5200RPM WD Blue drive). I know G5s are hot and I knew that when I decided to use it. Here in Ohio though it's now super hot and humid, and when this is running, my bedroom is an oven. I really don't want to go to a new Mac Mini or something, I want to keep my G5 as it's damn perfect for this, just a tad hot. So has anyone moded a PowerMac to take more fans or make it cooler in anyway?
     
  2. iModFrenzy macrumors 6502a

    iModFrenzy

    Joined:
    Jan 15, 2015
    Location:
    501st Legion
    #2
    I don't believe more fans will be the solution. I mean sure they help get rid of heat but that heat it gets rid of is still gonna heat up your room. All you'd be doing is making it more efficient in removing heat no?
     
  3. WalnutSpice thread starter Suspended

    WalnutSpice

    Joined:
    Jun 21, 2015
    Location:
    Canton, Oh
    #3
    Guess so haha. Thanks for making me sound stupid. Any ideas on making it generate more heat then? I've thought of redoing the thermal paste and cleaning the heat syncs but don't have the proper tools.
     
  4. Altemose macrumors G3

    Altemose

    Joined:
    Mar 26, 2013
    Location:
    Elkton, Maryland
    #4
    Any G5 is going to put out a lot of heat due to their nature. The G5 uses a special Torx screw driver that has a long shaft to remove the heat sinks, from there a standard computer repair tool set will handle the job. I do not recommend messing with removing the logic board and what not to change the U3 pads/paste unless you really know what you are doing. As for adding more fans, there is very little room in the case and any fans you do add would be noisy due to the lack of computer controlled cooling at that point.
     
  5. Dronecatcher macrumors 68000

    Dronecatcher

    Joined:
    Jun 17, 2014
    Location:
    Lincolnshire, UK
    #5
    I know I'm stating the obvious but when my 2.3 DP G5 was my main Mac (currently pushed aside by the Mighty Quad) I ran it in "Reduced" performance mode, otherwise the fans would continually kick in (calibration made no difference).
    For most things the speed drop wasn't noticeable and when I needed the extra horsepower for video converting, I'd change the setting back up....then leave the room!
     
  6. Altemose macrumors G3

    Altemose

    Joined:
    Mar 26, 2013
    Location:
    Elkton, Maryland
    #6
    If the thermal paste is bad the fans will constantly kick in to attempt to cool the heatsinks.
     
  7. Dronecatcher macrumors 68000

    Dronecatcher

    Joined:
    Jun 17, 2014
    Location:
    Lincolnshire, UK
    #7
    It's not as straight forward as that, the temperature readings are normal, I think there's a hardware fault. Not a pressing issue - it's all boxed up and in reserve.
     
  8. Hrududu macrumors 68020

    Hrududu

    Joined:
    Jul 25, 2008
    Location:
    Central US
    #8
    If you want to keep the airflow at its maximum, make sure the back end isn't too close to a wall/desk that prohibits air exiting and you can set a small desktop fan in front of the machine to help force air through. Keep in mind that moving air through the machine isn't going to keep the room cool. The CPUs, Power Supply, and GPU are still going to generate heat, you're just dissipating it faster.
     
  9. Altemose macrumors G3

    Altemose

    Joined:
    Mar 26, 2013
    Location:
    Elkton, Maryland
    #9
    It actually could be as straight forward as that. If the CPU has poor thermal conductivity with the heatsink, the heatsink will never fully heat up. The Mac will blast the fans to attempt to bring the CPU temperature down, and since the heatsink is not working effectively the fans must run continuously. I know that sounds a bit obtuse, but it is the same way that a car with a 195 degree thermostat actually can run cooler than a car with a 160 degree.
     
  10. Dronecatcher macrumors 68000

    Dronecatcher

    Joined:
    Jun 17, 2014
    Location:
    Lincolnshire, UK
    #10
    That would make sense if the CPU hits a critical temperature and the fans keep on going but in my case the fans would strike up before the CPU was anywhere near it's normal threshold.
    Also, even when on reduced power setting, certain non processor intensive actions would crank the fans, whilst other real processor intensive actions would leave the fans alone.
    When I boot from an ASD and run diagnostics (and fan calibration) 30% of the time it reports a CPU failure, so I figure something's not right.
     
  11. oi! Suspended

    Joined:
    Jan 10, 2016
    #11
    Yes, I've noticed there's a lot of that on this forum. Some might say too much.
    A cooler mac is a longer lived mac.


    You are right, the case is huge, yet space is limited inside. If there is a mount/bracket for extra HD/SSD's, behind the front mesh beside the ram sticks, this compromises air flow. Not a big issue where I live, but in summertime Ohio it might make a big difference.

    If it's not there, it looks to me like a slim 140mm fan could be slid in and fixed to the front mesh to increase air speed. Might be worth having a speed regulator in line, to fine tune between too hot and too noisy.

    You could try a PCI fan or 2, they move heat out of the case nicely.

    Have you considered externally mounted fans? You could fit two 150mm fans to the front of the case pretty easily, I like the Delta AFC1512DG, good air flow, good static pressure, noisy at full speed, I'd deffo fit an inline speed control to fine tune between too noisy and too hot.

    If you're brave and don't mind Steve Jobs turning in his grave, you could remove a chunk of that front mesh and either fit a wire type finger guard, or even leave an empty hole (I'd fit the finger guard) this should give a small improvement on the mac's already pretty good air flow.

    If you have a lottery win burning a hole in your mink trimmed silk and cashmere pockets, or you've simply run out of space to stack all those bundles of $1000 bills, you could have a liquid nitrogen cooling system and your very own cryogenic cooling plant. In the real world there's water cooling, but it carries risks, I personally no longer recommend this option (after a long and very serious chat with a mate who mostly tests high end PCB's for a living).





    OK, so that was about getting the heat out of the case, here are a few things that might reduce the heat.

    Running in Reduced mode, as suggested by Dronecatcher, is a good idea.

    Have you considered down clocking the graphics card and/or swapping in a cooler one?

    How many HD's do you have? What's the over all capacity? Can you fit fewer and/or cooler running drives?

    I'm not sure I'd actually recommend it, but only having two 256mb ram sticks should lower overall temp a little.

    Are there any PCI cards fitted that aren't actually in use, they kick out heat (some more than others).

    Lastly and definitely most sucky, you could swap it for a 1.6 single core machine, it runs the coolest. I think you might need to be very desperate to want to try this option
     
  12. Dronecatcher macrumors 68000

    Dronecatcher

    Joined:
    Jun 17, 2014
    Location:
    Lincolnshire, UK
    #12
    Another thing to consider is you've gone from the passively cooled 5200 to the 6800 with it's fan - that's more hot exhaust for you.
     
  13. Altemose macrumors G3

    Altemose

    Joined:
    Mar 26, 2013
    Location:
    Elkton, Maryland
    #13
    Think about it this way, if the thermal paste was in its optimum condition, the CPU would disperse heat evenly to the heatsink and run cool. With degraded and old paste, the CPU puts heat out in a spotty pattern, rather than uniformly. The machine then runs the fans to cool the "hot spots" on the bottom of the heatsink.
     

Share This Page