So this portion of the guide will only overview removal of the entire unit. Buy these tools. To avoid electrocution, shut down the computer. Do not open the computer or attempt to install any items inside it while the computer is on. To avoid being burned, wait at least 10 minutes to allow the computer's internal components to cool.
The panel should fall out. If the panel does not fall out by itself pull a little from the edges.
Power Mac G5 Processor and Cooling Unit Replacement
Apple inserted a rather fragile plastic pin that inserts through the top divider shield and clips into a tab on the hidden ledge of this CPU shield. Removing this pin, certainly voided Mac's warranty - but more appropriate for now, voids most after-market insurance plans. A replacement pin new is hard to get ahold of, and very few are talented and patient enough to remove this pin without damaging it.
Just something to keep in mind. If you have no warranty any longer or don't care, please continue Unplug the fan's power cable from the upper rightmost corner of the motherboard connection J If there is a video card in place, carefully pull the cable plug down between the back edge of the video card and the motherboard. Note, the photo shows the unplugged cable and the area it plugs into outlined in yellow. No video card is shown in this photo. While pushing in on the tabs, highlighted in yellow, pull the fan back towards the cooling unit. Put the CPU case on its back with the opening facing up to make the next steps easier.
Unscrew 8 T10 screws from the cooling unit. The prefered tool will be long handled allen keys. You may strip your tool or the actual screws themselves. Use a set of high quality long handled allen keys.
The screws will loosen but will not come out, they are designed to loosen the unit, but remain in place. The last two images show another version of the LCS out of the computer in the G5 with off-center views to show the 8 screw holes. The sleeves around the 6 screws may hold it in, if so just take a pair of needle nose pliers and gently squeeze the sleeves until it releases. Pull the bottom, then side towards the bottom of the CPU case, first to move around the bottom coolant sleeve around the heat sinking bracket.
Here are the standoffs without the cooling unit installed to make it easier to understand where the screws are located. Remove the bottom 2 standoffs so it is easier to remove the power supply. Check the pin connections for any damage. All the pins highlighted in yellow should appear straight up and not appear bent. A bent pin will result in your computer not powering on. I did not complete this guide.
I have a different cooling apparatus in my Quad Core than the one pictured here. It has a wider radiator on the left side and two black pumps on the right side.
The pumps are elevated away from the CPUs. I can only find 6 of the 8 screws mentioned in STEP The unit will not come out.
If the 2 remaining screws are as pictured in STEP 18, then they would be directly under my radiator. Do I need to remove that too? I have the same problem with a G5 Dual 2. I am about to loose it.
So I decided to take my little Dremel tool and simply cut off the part of the PCB, which held the active components. Then I also cut through the very fine traces leading away from the solder joints of the connectors at the firewire socket, at the USB socket. With a multimeter I validated that none of the relevant pads had remaining contact to any of the surroundings. In the same course of action I found three adjacent pads on the backside, which lead to the tiny power switch power LED three pin connector.
Next step was to find a set of cables with appropriate motherboard ATX pin headers. A tie wrap by the end keeps the harness in place without stress to the delicate solder points of the wire tips. I figured out that the trouble maker is the fact, that the Apple circuitry uses a common lead for the switch and the LED return. So ideally a 4 wire connection would be best, well not an option here. The little circuit is shrink wrapped to the post type header. See some illustrations below.
Power Mac G5 Processor and Cooling Unit Replacement - iFixit Repair Guide
Remaining test will be to try the firewire front connector. Finishing touches: The divider frame of the original Mac is obviously designed around the original motherboard, with the mATX board in place the memory slots and some other components do collide a bit. So I had to trim the divider frame at the motherboard side to provide enough clearance and I added a little sheetmetal bracket at the far end to line up with new ATX mount point. By adding a few washers to simulate the thickness of the motherboard the divider frame now sits exactly where it was in the first first place.
The frame snaps back in place being held by 3 out of 4 legs and on the inside there is even enough clearance to mount fans. I decided to leave additional fans as option for the future, I also left this intake side without any fans for now. Instead I am using a giant beQuiet cooling tower with a single mm fan and expect it will give me enough flow through the tunnel, considering both ports being completely open. One of the fans is a radial blower geared at the G5 heat pipe on the bottom side of the motherboard, that is simply obsolete, cause there is no active circuitry on the backside of an ATX board.
This opens the opportunity to feed the power supply harness for the drive under the motherboard through an existing hole of the drive bay compartment, no metal work required! The second fan creates some flow across the drives, frankly I am using an SSD as boot drive which does not run as hot as a hard disk, so I can get away without any fan in the top level compartment.
Yet I have put the empty frame back in place to keep the outer appearance. What the radial blower removal also gives you is a very straight forward routing path for the SATA cables to the mother board, otherwise it would be real tight I the upper compartment! I did add a silent 80mm fan for the PCI extension area, mounted it to the original frame, set up as case fan to the mother board socket, done.
So finally my conversion is complete: And side by side before and after: The whole work is very doable over a weekend, provided tools, some sheetmetal and parts available, the bigger thing though is to study other completed modifications ahead of time and take advantage of knowing the traps you may want to avoid BEFORE you spin up the Dremel tool. A few hints and tricks which might be useful for other folks: Yet the nice drive door mechanism of the Mac case does not give you access to the physical button!
I found several free utilities for Win to help this, personally I have installed HiCDEJECT, which simply adds a little icon in the info tray of Win, touch it and the tray opens and closes Dual boot messes with time zones! Go fix this by having Windows also reference to UTC, it merely is a minor change in the registry.
By the end I figured out, that the little blower is only snapped in place on 2 studs, so gently pull it up and THEN take the bottom mounting screws out of the chassis, the separated pieces can be taken out just easily. The G5 front panel is also snapped in place rather than held down with a couple of screws. Took me a while to get it off: Take a little metal tube with a 4mm diameter, push it gently over the ends of the clamping studs to release the front panel, it comes off in seconds!
Clean Power Mac G5 Conversion - my second turn
Saw service instruction videos grabbing the ends with pair of pliers, did not work for me, cause you really need the grab the four prongs of the clamp studs in one go all around. Taking out the original processor module from the motherboard was another little tricky part: You need some really really long Allen drivers to reach through the big and high cooling tower to the bottom 2 center bolts, my local hardware store did not have those extra long thingies on stock.
Standard bit holder type of tools however are to big to enter the hole in the cooling tower. Well, I helped myself by simply taking a stand alone Allen bit, grinded a slot into the back of the bit.