Preface
This is the mod where i converted a PowerMac G5 2.5 GHz Liquid Cooled computer into an Air cooled computer. Using traditional G5 heatsinks, I attached them to the 2.5 GHz cpu’s and put them into the G5.
Also more information on what I did can be found on this iFixit website
I revisit this mod once again but this time i install a new logicboard and processors for all to see the steps i did.
Rear shot of the G5 DP 1.8 GHz
Front shot of the G5 1.8 GHz
Inside shot
Original case and guts, 1,8 GHz Dual Processor
Stock Nvidia 5200 64 MB video card
Fans removed
The model number for the dual 1.8 GHz board
630-6691
The original heatsinks for this mac
Heatsink model number A
Heatsink model number B
The stock Nvidia 5200 64 MB
Loosen these allen screws 5 turns
And these two
And these ones
This one too
Don't forget about this one
Last but not least, this one also
CPU A pulled out
CPU B pulled out
Processors removed
630-6633/T6662 CPU A (PowerMac G5 1.8 GHz)
630-6633/T6662 CPU B (PowerMac G5 1.8 GHz)
Both 1.8 GHz CPU's side by side
Apple 820-1592-A to be put in
This is the 630-6692 board. For a dual 2.3 GHz G5, all the important info about it
The replacement board
New CPU's
New heatsinks to be put on. I couldn't find a match
Top of the new heatsinks
This is what was supposed to cool the CPU's i'm putting in
Heatsink 630-6682 #1
Heatsink 630-6682 #2
630-6464/T6489 (PowerMac G5 2.5 GHz) CPU A
630-6464/T6489 (powerMac G5 2.5 GHz) CPU B
Both together
Old vs new, 2.5 GHz has a taller rear pipe
Old heatsink with copper core
Old heatsink with copper core
New heatsink with heat pipes
To remove old logicboard, I removed the PCI brace first
Unplugged the speaker and fan
PCI fan pulled out
Heatsink standoffs to be removed
Gently used a pair of pliers and twisted counter clockwise
Just enough to be unscrewed by hand afterwards
Unscrewed the rest of the way by hand
First few removed
They all need to be removed in order to remove the logicboard
All standoffs removed
Use a screwdriver to remove these last screws
Almost out
Pull out by hand and repeat for the other side
Unplug IDE cable
Gently remove cap for front panel cable
Gently unplug front panel cable. Careful, it will break easily
Rear fan assembly comes out next
Push in the two tabs and the fan pops out
All fan and SATA cables unplugged from board
Rear fans removed
Motherboard screw #1 to be removed
Motherboard screw #2 to be removed
Motherboard screw #3 to be removed (this one holds the PCI divider in place)
Motherboard screw #4 to be removed
Motherboard screw #5 to be removed
Motherboard screw #6 to be removed
Unplug power socket A
Unplug power socket B
Unscrew PSU cover screw #1
Removed and set aside
Unscrew PSU cover screw #2
Removed and set aside
Lift up on the PSU cover
Start pulling up at an angle
Only way it comes out is if you bend it slightly
Pulled out and set aside
PSU cover removed
Power socket C location
Unplug power socket C
Bottom 2 of 4 PSU screws to be removed
Bottom 4 out of 4 PSU screws to be removed
Removed and set aside
Removed and set aside
Slide PSU forward and start to lift up at an angle
Once lifted out at an angle, PSU just pops out
PSU removed
Inside the PSU area
LiteON 600W, one of the better PSU's for a G5
Grab board by PCI divider and pull slightly towards the front of the case to remove
Lift at a slight angle and the board comes free
Inside the case. I added a couple of old G5 rubber braces to sit under the CPU sockets for support
Remove these screws to take off PCI divider from board
This screw also comes out
Unplug the fan connector from the logicboard
PCI divider free
Old vs new logicboards
Slight differences on the underside
New board has a heatsink on this chip
New board has copper on this chip
Old board has aluminum on this chip
PCI divider attached to new board
Plug front fan connector into socket close to Airport slot
The other connector is what the old liquid cooler plugged into (nothing goes there now)
New board put into case (reverse on how you took out the old board)
Plug in the IDE cable
Plug in the fan and SATA connections
All connections plugged in. And screws holding the board in place are put in too
Slide PSU in at an angle
Once it pops in, slide it back a little and it will seat properly
Plug in power socket C
Plug in power socket A
Plug in power socket B
Put in PSU cover. With a little effort, it does go in
It will sit flat, readjust to put the screws back in
Screws back in place
Bottom PSU screws back in place to hold PSU
Slide PCI fan back in place
Reconnect speaker and fan plugs
Put back in PCI bracket and it's two screws
Replace the cards you took out from the old board
Ram going into the machine
8 sticks of ram, to be installed, ram has to be in pairs
More ram
More ram
More ram
First pair (sockets A1 & B4)
Second pair (sockets A2 & B3)
Third pair (sockets A3 & B2)
Fourth pair (sockets A4 & B1)
All four CPU's sitting together
Rear heat pipe differences
The 2.5 GHz CPU's have copper on the bottom, the 1.8 GHz have aluminum
Old CPU's set aside. We will be working with these ones
New heatsinks. Too bad they both didn't have copper bases
New heatsinks side by side
This is what the old heatsink looked like
Reinstall rear fan bracket
Plug in it's connector near the SATA ports
Arctic Silver 5 used on this project
Standoffs and screws to be put back in
Going back into their original spots. Tighten but don't snap them off
All put back into place
Just a dab on CPU A
Same with CPU B
Start with CPU A. I put it on the aluminum heatsink
Make sure it sits flush and properly with the plastic board holders
Reinstall CPU screws, tighten in X pattern until snug. Do not over tighten
Screws snug
Screw in screws that hold the CPU board into place
Finished CPU
Rear pipe as tall as the heatsink
Put this CPU in the bottom socket
Now work on the next CPU
Tighten screws in X pattern until snug. Remember, do not over tighten
Screws holding board onto heatsink in place
Plug this CPU into the upper socket
Replace front fans
Make sure the front panel plug is plugged in or no power button
Also replace plastic cap on front panel plug
Put baffle back into place. Start up machine to see if it chimes and boots. If so, take allen screwdriver and tighten standoff screws so CPU's don't shift. Tighten until snug
Once everything works, put plastic spacer and cover for the heatsinks
Replace front fans and baffle. Put side back on machine and boot up
Before you use this machine, you will need to recalibrate your CPU's by using the AHT 2.5.8 CD from Apple
