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MrVitalic

macrumors regular
Original poster
Mar 16, 2020
164
195
It first started when I bought a quad core logic board to fix my broken dual core g5. Then I said to myself: wait a minute, I could convert my dual to quad! Then soon, I bought a quad with a broken lcs. Then I said to myself: wait a minute, I coud convert my quad to air cooling !!

So here ya go. From the look of it, the 2.3ghz heat sink is wayyyy better than the 2.0 one. I have both , and for the moment, this is what I used to cool my quad (I have a second 2.3hs coming my way). My first idea was to make a quad 2.3 but right now I'm testing a quad 2.5.

IMG_3222.jpg



First drawing the part (mesure taken from a digital caliper on a rough casting):
Screen Shot 2020-04-04 at 9.45.37 AM.png


The red line represent what I'm modifying(cutting) from the original heat sink to fit two of them side by side. The support bar already have all the thread needed (thx apple, I'm sure you tried but made the heat sink wider to prevent user to make a air cool swap. Just look at the casting you'l understand what I meant)

Then cutting on a wire edm. I had a bad luck and lost two hour. I first thought the casting was steel by the look of it (and weight from the whole assembly), then maybe stainless steel because it was non magnetic....A wire cutter can be hell when wire breakage happen at random. So... after investigation, I think the plate is made from magnesium. I never machined that alloy but but but, that fck thing, when I knew what this was, all hell broke loose:
IMG_3234.jpg


Ready for the next part! (2h cut)

IMG_3243.jpg



Note that I made the clearance for the 'G5' cover nipple.

Assembly: Everything work but you have to install the secondary heatsink(vrm) in a separate step (last). Also, the middle stand off screw wont screw because of the coper plate.

IMG_3245.jpg



OMG I'm jumping around! My ****** **** work. I'm listening to some good techno. installing the cpu: no issue.
IMG_3246.jpg


YES VICTORY

IMG_3250.jpg


The potatoe 2.0hs is not performing well. My 2.3 hs keep eveything below 60c, while the other keep everything over 70c. So the fan rev hight in a tress test.

IMG_3252.jpg


My second 2.3hs is coming my way. I think this machine wil be very tame when this fella is installed. For general purpose, this G5 is very quiet atm with this miss matched hs set-up.

Heres the link for the dxf (https://drive.google.com/open?id=1XjggJ0SzMm6wU1cJsviD0pL1Py8jnZc0)
Useful if you have a machine shop near by, that can do wire cut to modify your heat sink (dont know about water cutter but ask them).
 
Last edited:

AshleyPomeroy

macrumors member
Dec 27, 2018
87
173
England
This is like that chap who used to post here about overclocking his G5, except that you've posted pictures with instructions and examples etc, whereas he didn't. Good work!

It's frustrating that the two most powerful G5s used liquid cooling. They're attractive on the used market because they're the last of their kind, but they're a reliability concern. It's like the first-generation PlayStation 3, the one that could run Linux - you'd be continually worried that the cooling system would break.
 

MrVitalic

macrumors regular
Original poster
Mar 16, 2020
164
195
This is like that chap who used to post here about overclocking his G5, except that you've posted pictures with instructions and examples etc, whereas he didn't. Good work!

It's frustrating that the two most powerful G5s used liquid cooling. They're attractive on the used market because they're the last of their kind, but they're a reliability concern. It's like the first-generation PlayStation 3, the one that could run Linux - you'd be continually worried that the cooling system would break.

Thx! Yes in my google research I found a lot of thread from rabidz... he once said on reddit that he hacked apple server to get board shematic, while posting on other group about datura and various others drugs...

I tried to run asd 2.6.3 without the lcs plugged and got an error message right away. I’l do more testing when my second hs is ready. ( Running thermal calibration on this must be the same procedure as converting a dp to air cooling with the lcs attached only to pass asd).

I tried to fix the lcs, but I gave up pretty quick. The hoses glued with epoxy are very hard to remove. And now, this is a worry free mac.

I dont want to spend too much on this machine but my next upgrade would be a owc 120gb sata 2 ssd, digidesign pcie hd accel core (this machine will be my new protools rig when ready) and fixing my bricked evga 7800 gtx ko. For the 7800 I tried to flash a ppc 7800 gt rom on it but the file was too big for the eeprom :/ . I’l solder a eeprom sourced from a junk mac 7300gt and try flashing again.I tried to make a custom rom last year but oh boy, thats tough.
 

MrVitalic

macrumors regular
Original poster
Mar 16, 2020
164
195
Oh and If you guys wonder why I’m working this hard on a old mac when I own two macpro... I’m tired of keeping up with technology, I love using old gear, I dont want this mac to end up in trash or be converted to a hackintosh, and for what its worth, its very competent at making music. And the cpu score of a quad G5 is in the sweet spot for my need in audio.
 

z970

macrumors 68040
Jun 2, 2017
3,582
4,449
I dont want to spend too much on this machine but my next upgrade would be a owc 120gb sata 2 ssd, digidesign pcie hd accel core (this machine will be my new protools rig when ready) and fixing my bricked evga 7800 gtx ko. For the 7800 I tried to flash a ppc 7800 gt rom on it but the file was too big for the eeprom :/ . I’l solder a eeprom sourced from a junk mac 7300gt and try flashing again.I tried to make a custom rom last year but oh boy, thats tough.

Sounds like you've got the most badass Quad in existence...

Our greatest congratulations to you. :)
 

fourbirds

macrumors member
Jan 12, 2019
64
71
Just a quick note about the liquid cooling system on the quad G5. Not to take away from the really cool accomplishment of OP but the dual pump LCS is pretty reliable. No o-rings to go bad and no leakage as the system is a closed loop. The cooling blocks do eventually clog up but that can be taken care of by draining the system and refilling it making sure to purge the loops of any air. That's what I did with mine and I'm getting consistent mid 20s to low 30s Celsius temperature at idle.
 

Alexis Trinquet

macrumors member
Mar 1, 2020
68
67
Gouvieux, France
Holy cow, that's some real awesome stuff there!

Now I'm tempted to buy a Quad 2.5 and converting it to phase-change cooling (=replace the LCS with one of those "Chillers" coolers), but I don't see this happening anytime soon.
 

MrVitalic

macrumors regular
Original poster
Mar 16, 2020
164
195
Holy cow, that's some real awesome stuff there!

Now I'm tempted to buy a Quad 2.5 and converting it to phase-change cooling (=replace the LCS with one of those "Chillers" coolers), but I don't see this happening anytime soon.

These new cooler are very cool. From what I understand they are made of looped heatpipe. Ive seen LTT video about the prototype and it look promising.

Just a quick note about the liquid cooling system on the quad G5. Not to take away from the really cool accomplishment of OP but the dual pump LCS is pretty reliable. No o-rings to go bad and no leakage as the system is a closed loop. The cooling blocks do eventually clog up but that can be taken care of by draining the system and refilling it making sure to purge the loops of any air. That's what I did with mine and I'm getting consistent mid 20s to low 30s Celsius temperature at idle.

No probs, I repeat myself, but the reason why I never used water cooling on anything is because I dont want to worry about flushing the loop and all the maintenance. For the performance of the heatsink in this G5, it idle at 28c (room temp at 22c).
 

fourbirds

macrumors member
Jan 12, 2019
64
71
No probs, I repeat myself, but the reason why I never used water cooling on anything is because I dont want to worry about flushing the loop and all the maintenance. For the performance of the heatsink in this G5, it idle at 28c (room temp at 22c).

That's impressive! Mine iddles at 32c in the summer months and around 27c in the winter. So yours is already performing better than the stock liquid cooling.
 
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MrVitalic

macrumors regular
Original poster
Mar 16, 2020
164
195
That's impressive! Mine iddles at 32c in the summer months and around 27c in the winter. So yours is already performing better than the stock liquid cooling.

I may have been too optimistic, after a while it settle to 30c ( still good). My theory about why apple did use a lcs is thermal paste technology was not as advance in 2005 compared to what we have today. Some people still use artic silver 5 when it is not as efficient as other. Artic mx4 is very good so is gelid gc extreme and now thermal grizzly make the cream of the crop. Last year I bought localy some cheap paste that had a rating of 5 w/mk when I ran out of mx4. It was so bad that I couldnt pass the thermal calibration test when I upgraded my dc 2.3 to 2.5 (was idling at 42c).
 

MrVitalic

macrumors regular
Original poster
Mar 16, 2020
164
195
little update:

from left to right, original quad fan, modded fan, and another modded fan from a dc 2.3 that I grinded to make room for the psu logic board connector. It is not perfect but maybe when I have time, I'l make something more professional on a cnc milling machine (didnt have time tonight)

IMG_3270.JPG

IMG_3272.JPG


The air duck is a hit or miss... Dont know If I will keep it or just forget about it.

IMG_3274.JPG

IMG_3278.JPG


Its a tight fit in there

IMG_3277.JPG
 

MrVitalic

macrumors regular
Original poster
Mar 16, 2020
164
195
Man, that's the coolest G5 in the world...

How's it drive?
Thx I really appreciate :) I have a tendency of being a bit over the top when working on a project. For the quad it look promising but I’m still testing it. My hdd is slow (worn out 160gb velociraptor 10k) so its hard to judge and I didnt tried ableton, renoise or protools yet. Gaming is not stellar because the 6600 le but I’l try to unbrick my evga 7800gtx next weekend (by flashing a 7800gt rom on a macpro 7300gt then solder that eeprom on the 7800gtx... I dont have a eeprom programmer so)

Pardon my rambling :p Anyway, so far it is not noisy , a bit more compared to my macpro 2.1 8core but nothing compared to the broken quad the 8bit guy tested lol
 
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MrVitalic

macrumors regular
Original poster
Mar 16, 2020
164
195
For your interest, I found a compatible ssd. With shipping, ordering a ssd from owc cost a lot (about 130$). I’m glad I found an alternative. This is my bootcamp drive but I’l clone it on a platter hard drive. I tried a kingston ‘ssd now V300’ but it doest appear in 10.5. Note that I’m always using western digital velociraptor caddy for my ssd, because they are cheap, all aluminium and they look very cool.
325D2491-5B20-4F5C-8E70-D4134021337A.jpeg

BD6C7A6E-FFC3-4018-AE70-7C6A007CA707.jpeg
 

MrVitalic

macrumors regular
Original poster
Mar 16, 2020
164
195
Heres my final update on this project. I bought a second 2.3 hs as mentioned before.


Doing this a bit clandestine while I'm doing overtime alone : another night, another heatsink...
IMG_3344.jpg


I'v added the rubber bumper for the G5 plate onto the heatsink.
IMG_3348.jpg


As a machinist, I love symmetry. 16 heat pipes total. 8 on front, 8 on back.
A
IMG_3350.jpg


This is the end. They both max at 63 celsius when pushed at max by power fractal (100% usage on 4 core), with obviously the fan running faster but nothing that I would call extreme. On regular task ( ableton so far) the mac hum along.

To share, heres some of the music I love at the moment
 

Doq

macrumors regular
Dec 8, 2019
213
331
The Lab
You know, I thought about getting a Quad and then doing custom watercooling on it but you know what this is even better! Gonna consider this (although, a custom hardline loop making a "G5" in tubing still sounds dope to me) when I go perusing the markets.
 
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starmax

macrumors newbie
Mar 22, 2011
23
16
Very interesting! I recently acquired a 2.3 dual core and have been researching how to convert it to a quad core. I am a bit gun shy on using the apple LCS, but I am no machinist either! Wondering if mid 2004/early 2005 air coolers would work, but they are much smaller than late 2005 ones...
 

Macbookprodude

Suspended
Jan 1, 2018
3,306
889
Just a quick note about the liquid cooling system on the quad G5. Not to take away from the really cool accomplishment of OP but the dual pump LCS is pretty reliable. No o-rings to go bad and no leakage as the system is a closed loop. The cooling blocks do eventually clog up but that can be taken care of by draining the system and refilling it making sure to purge the loops of any air. That's what I did with mine and I'm getting consistent mid 20s to low 30s Celsius temperature at idle.

I digress.. tHE single pump is the most reliable and I can find the source of that. The dual pump on the Quad was not so reliable. 2 sometimes isn't reliable, though you would think it is. I myself have the single pump for my Quad and it never gave me an issue and I have had the machine for 11 years. Bought in 2009 kinda new like. I also did many reboots and re-starts and the thing just keeps going. Very reliable machine, however, its in a box right now due to the fact, that it would eat my electric bill as I moved from a room to an apartment where now I am paying 880.00 vs 530.00 for everything.
 
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LarsG5

macrumors member
Aug 10, 2016
49
13
Hi, congrats on your project.
Which heatsink is 2.0 and which one is 2.3?
 

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